Friedrich Engels was born 200 years ago today on Nov. 28, 1820. Together with his friend Karl Marx, who was two-and-a-half years his senior, Engels co-founded scientific socialism. Two hundred years later, their life’s work is of burning contemporary relevance. They were much more farsighted than the countless academics who have filled entire libraries with their attempted refutations of Marxism.
Financial markets totally out of control; trade wars threatening to erupt into a third world war; the destruction of entire regions of the world by brutal neocolonial wars; the disintegration of democracy in the most important capitalist country, the United States; a looming environmental catastrophe; the entirely avoidable deaths of hundreds of thousands due to the coronavirus pandemic; a level of social inequality such that 26 individuals possess as much wealth as the poorest half of the global population—all of this confirms that “modern bourgeois society,” as Marx and Engels wrote in the Communist Manifesto in 1848, is “like the sorcerer who is no longer able to control the powers of the nether world whom he has called up by his spells.”
Marx and Engels did not confine themselves to analysing the contradictions of capitalism and predicting its downfall. They were both revolutionaries. One cannot understand their theoretical work if it is separated from their political and revolutionary activity. What distinguished them from all previous socialists, petty-bourgeois democrats and other critics of the political setup was the insight that only the conquest of power by the working class, the only “truly revolutionary class” in bourgeois society, could prevent a relapse into barbarism, abolish the division of society into classes, and lay the basis for a tremendous leap forward in human civilisation and culture.
Engels stressed this point when he spoke at his friend’s grave in 1883, stating:
For Marx was before all else a revolutionist. His real mission in life was to contribute, in one way or another, to the overthrow of capitalist society and of the state institutions which it had brought into being, to contribute to the liberation of the modern proletariat, which he was the first to make conscious of its own position and its needs, conscious of the conditions of its emancipation. Fighting was his element. And he fought with a passion, a tenacity and a success such as few could rival. 
The same applies to Engels himself. In 1935, 40 years after Engels’ death, Trotsky painted a portrait of him in a brilliant essay in which he compared Engels to Karl Kautsky, who worked alongside Engels in London for many years, rose to become one of the leading Marxist theoreticians of the Second International, and ultimately emerged as a bitter opponent of the October Revolution.
Engels saw even then in Kautsky, according to Trotsky, “a Viennese petty-bourgeois, self-satisfied, and egotistical and conservative.” He helped Kautsky and Eduard Bernstein, who also spent time in London, “to acquire the Marxian method.” Trotsky continued: “But he could not ingraft in them either revolutionary will or the ability to think boldly. The pupils were and remained the children of another spirit.” “Throughout his entire and lengthy life, Kautsky was able to circumnavigate those conclusions that threatened to disturb his mental and physical peace. He was not a revolutionist, and this was an insurmountable barrier that separated him from the Red General [Engels],” wrote Trotsky. 
Engels’ contribution to Marxism
Engels’ contribution to the development of Marxism is often underestimated. He himself admitted, without any trace of envy, that he played the second violin during Marx’s lifetime. But one must add that he mastered it no less wonderfully than Marx did in playing the first, and that their interplay gave them the mutual inspiration to continually reach new heights of achievement.
It would be impossible “to find a parallel instance of two men of such powerful temperaments and ideological independence as Marx and Engels who remained throughout their entire lives so indissolubly bound together by the evolution of their ideas, their social activity and personal friendship,” Trotsky observed. The cooperation of the two friends was so wide-ranging “as to make it impossible for anyone ever to establish the line of demarcation between their works. However, infinitely more important than the purely literary collaboration was the spiritual community that existed between them, and that was never broken… For some four decades, in their continual struggle against official science and traditional superstitions, Marx and Engels served each other in place of public opinion.” 
Engels made an important contribution to their common world outlook in particular in the field of political economy and the understanding of the revolutionary role of the working class. Due to his family background and his thirty-year business career, and his thorough knowledge of the workers’ movement in England, the leading industrial power at the time, he possessed first-hand knowledge on these issues. In addition, he had an encyclopedic mind—he mastered actively or passively over two dozen languages. “His knowledge of philosophy, economics, history, physics, philology and military science would have sufficed for a goodly dozen of ordinary and extraordinary professors,” as Trotsky remarked. 
Engels was born the eldest of nine children of a textile businessman in Barmen, which is today a district of the city of Wuppertal. He attended a gymnasium, but was forced to break off his studies in his final year by his father, who wanted him to begin his business apprenticeship in his company. From the summer of 1838, he continued his training in cosmopolitan Bremen for three years, where his literary career also began. Engels published the “Letters from Wuppertal” under a pseudonym in the left-liberal Telegraph für Deutschland, in which he settled accounts with the ingrained piety of his home region and his parents’ household, and laid bare the social misery facing the industrial workers.
Shortly before his 21st birthday, Engels went to Berlin for a year, officially to complete his military service. However, he focused on an intensive study of philosophy and made close contact with the Young Hegelians. He continued his literary work. He wrote for, among other publications, the Rheinische Zeitung edited by Karl Marx, but had no personal contact with Marx apart from one brief encounter. The young Engels made an impression in the field of philosophy. He triggered considerable uproar with two anonymously published outstanding polemical essays against the irrationalism of Schelling, who had taken over Hegel’s chair at Berlin University.
In late 1842, Engels went to work for his father’s company in Manchester. He used his time there to engage with classical political economy, study the condition of the working class, and enter into close contact with the British workers’ movement. This was also the period when he fell in love with Mary Burns, an Irish worker, who remained his partner until her early death in 1863.
Several months prior to Engels’ arrival, the Chartist movement reached its peak. With 70,000 members, it was the first mass political movement of the working class anywhere in the world. The Chartists collected 3.3 million signatures on a petition presented to the House of Commons calling for universal suffrage for all men over the age of 21 and a series of social reforms. The rejection of the petition by the House of Commons triggered a series of strikes that were brutally suppressed. Engels became friends with the left-wing Chartist leader Julian Harney and wrote for his newspaper, the Northern Star. He also had contact with the followers of Robert Owen’s utopian socialism.
Then, in early 1844, the 23-year-old Engels published the article Outlines of a Critique of National Economy, which had a major impact on Marx. It was the first attempt to base the justification for socialism on political economy instead of on ethical or moral postulates. In the article, Engels examined “the principal phenomena of the contemporary economic order from a socialist standpoint, regarding them as necessary consequences of the rule of private property,” as Lenin later wrote in an obituary of Engels. 
One year later, Engels summarised his observations in the book The Condition of the Working Class in England, which Marx would later draw upon in the writing of Capital. He portrayed the proletariat not simply as a suffering class, but rather as a fighting class, as the bearer of the socialist revolution.
Engels’ Outlines of a Critique of National Economy appeared in the first—and only—edition of the Deutsch-Französische Jahrbücher, which Marx and Arnold Ruge assembled in Paris after being forced to flee from the reactionary Prussian state. In the same volume, Marx published the article Critique of Hegel’s Philosophy of Right, a milestone in his break with Hegelian idealism.
Collaboration between Marx and Engels
The close cooperation between Marx and Engels, which would last until Marx’s death 39 years later, began at this point. On his return trip from Manchester, Engels met Marx in Paris for 10 days of intensive discussion, which resulted in agreement on all important questions. A result of this discussion was The Holy Family: Critique of the Critical Critics, a ruthless settling of accounts with the Young Hegelians, which was published under a joint byline in early 1845.
The Young Hegelians, who cast themselves as incredibly revolutionary, advocated criticism that stood above all classes and parties, rejected all practical activity, and viewed the working class contemptuously as an uncritical mass. Both anarchism and the “critical theory” of the Frankfurt School would later base themselves on the Young Hegelians. Their “demand to change consciousness amounts to a demand to interpret reality in another way, i.e., to recognise it by means of another interpretation,” Marx and Engels wrote scornfully. 
“(I)n spite of their allegedly world-shattering statements,” the Young Hegelians, Marx and Engels further noted, “are the staunchest conservatives.” They forget that they “are in no way combating the real existing world when they are merely combating the phrases of this world.”
The above citation is taken from The German Ideology, a comprehensive work jointly written by Marx and Engels in Brussels in the winter of 1845–46, where Engels had by then joined Marx. It continued the criticism of the Young Hegelians and expanded it to include Ludwig Feuerbach. Feuerbach was the first to criticise Hegel’s objective idealism from a materialist standpoint and thus exerted considerable influence on Marx and Engels. But his materialism excluded human practice and thus remained contemplative, passive and ahistorical.
In The German Ideology, Marx and Engels elaborated the materialist conception of history upon which their later masterworks were based. This conception of history
depends on our ability to expound the real process of production, starting out from the material production of life itself, and to comprehend the form of intercourse connected with this and created by this mode of production (i.e., civil society in its various stages), as the basis of all history… to explain all the different theoretical products and forms of consciousness, religion, philosophy, ethics, etc. etc. and trace their origins and growth from that basis…
[The materialist conception of history] does not explain practice from the idea but explains the formation of ideas from material practice; and accordingly it comes to the conclusion that all forms and products of consciousness cannot be dissolved by mental criticism… but only by the practical overthrow of the actual social relations which gave rise to this idealistic humbug; that not criticism but revolution is the driving force of history, also of religion, of philosophy and all other types of theory. 
A revolution occurs when the “material elements” are sufficiently strong—“namely, on the one hand the existing productive forces, on the other the formation of a revolutionary mass, which revolts not only against separate conditions of society up till then, but against the very ‘production of life’ till then, the ‘total activity’ on which it was based.” 
Marx and Engels did not succeed in publishing The German Ideology, which appeared in full only in 1932. But they had achieved their most important goal: self-clarification. The work on The German Ideology led to the greatest political programme ever written, the Manifesto of the Communist Party. In 1847, Marx and Engels joined the League of the Just, in which numerous German exiles were active. The League had invited them and agreed to change its name at their request to the Communist League. Marx and Engels were commissioned by the League to write the manifesto.
It is a great challenge to do justice in a few sentences to this work, which continues to impress the reader today with its clarity, farsightedness and boldness. In it, Marx and Engels sketch in a few broad strokes the dynamic development of the capitalist system, which is tearing down all regional and national boundaries, exacerbating class contradictions, and ultimately proving incapable of controlling the forces it has set into motion. “But not only has the bourgeoisie forged the weapons that bring death to itself; it has also called into existence the men who are to wield those weapons—the modern working class—the proletarians,” wrote Marx and Engels.
There follows a revolutionary socialist programme, whose fundamental features have retained their validity to this day. Its central thrust is the political independence of the working class and its international character. The Manifesto includes a sharp critique of all previous forms of socialism—utopian, petty-bourgeois, and bourgeois—and defines the tasks in the democratic revolution that was about to break out. It concludes with the famous declaration, “Workers of the world, unite!”
The revolution of 1848
The Communist Manifesto appeared in London on Feb. 21, 1848. Three days later, a revolutionary uprising in France overthrew the monarchy. The revolution spread to Germany in March and rapidly expanded across Europe. The feudal rulers of the German states were forced to abdicate in droves or accept parliaments and constitutions. In May, the National Assembly began meeting in the Paulskirche in Frankfurt, where it was to draft a constitution for a united Germany.
Marx and Engels did not hesitate for a moment to participate in the revolution. Drawing on the tradition of the Rheinische Zeitung, which was banned in 1843, Marx and Engels founded the Neue Rheinische Zeitung (NRZ) in Cologne. Three hundred and one editions of the paper appeared between June 1, 1848 and May 19, 1849, and the publication reached a circulation of 6,000, a considerable number at the time. The newspaper saw itself as the left wing of the democratic camp and its task as pushing forward the bourgeois revolution, which, as the Communist Manifesto had declared, “will be but the prelude of an immediately following proletarian revolution.”
The amount of work carried out by Marx and Engels to publish a daily newspaper with the primitive technical facilities available at the time is almost impossible to comprehend. Engels traveled across the country to raise money and sign up subscribers, while contributing numerous articles. As editor-in-chief, Marx was the driving force of the editorial board. Financial problems confronted the project from the outset—especially after Engels in the first edition bitterly denounced the National Assembly deputies in the Paulskirche, who argued over the agenda and insisted on the strict observance of meal breaks as revolutionary fighters in neighboring Wiesbaden were shot down by Prussian bullets.
But the NRZ did not relent in its criticism of the bourgeois liberals, which soon united with feudal reaction against the revolution, nor of the petty-bourgeois democrats. Engels later summarised the experiences of this period in the book Revolution and Counter-Revolution in Germany, which originally appeared as a series in the New York Daily Tribune. To this day, it remains one of the best accounts of the revolution of 1848.
In the book, Engels issued a condemnation of the Frankfurt National Assembly that the German “democratic” petty-bourgeoisie has confirmed ever since: “This Assembly of old women was, from the first day of its existence, more frightened of the least popular movement than of all the reactionary plots of all the German Governments put together.” 
In March of 1850, Marx and Engels summarised the political lessons of the revolution of 1848 in the Address of the Central Committee to the Communist League, which would go on to have a major impact on Trotsky’s theory of permanent revolution. They insisted on the complete political independence of the working class from the petty-bourgeois democrats:
The democratic petty-bourgeois, far from wanting to transform the whole society in the interests of the revolutionary proletarians, only aspire to a change in social conditions which will make the existing society as tolerable and comfortable for themselves as possible… [the workers must] contribute most to their [own] final victory, by informing themselves of their own class interests, by taking up their independent political position as soon as possible, by not allowing themselves to be misled by the hypocritical phrases of the democratic petty-bourgeoisie into doubting for one minute the necessity of an independently organised party of the proletariat. Their battle-cry must be: The Permanent Revolution. 
London and Manchester
After the NRZ was banned, Marx and his family went into exile in London. Engels joined revolutionary forces in Baden who were fighting the advancing Prussian army. As an adjutant to August Willich, who would later serve as a general on the side of the Union forces in the American Civil War, he participated in three battles. He then traveled through Switzerland and Italy and also went to London.
The first decade of exile was dominated by serious financial difficulties. Marx and Engels were not prepared to make their peace with the democrats who had betrayed the revolution and were being celebrated in their London exile as heroes. Engels returned to his job as a business clerk in his father’s Manchester factory in order to finance his livelihood and support Marx, which allowed Marx to concentrate on the work for Capital. Engels’ wage was modest at first, but later he received a share in the firm. In 1870, he was able to sell his share for a price that secured his economic situation and enabled him to support Marx’s family. Even after Marx’s death, Engels continued to support his daughters, who inherited a large portion of his wealth.
Marx and Engels lived in different cities for almost 20 years. But they maintained an almost daily exchange of ideas in letters, through which they continued their intensive theoretical and political collaboration. Marx drafted his main work, Capital, in close cooperation with Engels, whom he often asked for advice due to his expert knowledge. Without the unbounded friendship and support of his friend, Marx would have never been able to complete his world historic work.
The first volume of Capital appeared in 1867. The second and third volumes were incomplete when Marx died in 1883. Engels assumed responsibility for their completion and publication. Trotsky described how fastidiously and carefully he conducted this work:
Engels not only deciphered, polished, transcribed, corrected and annotated the second and third volumes of Das Kapital, but he maintained an eagle-eyed vigil in defence of Marx’s memory against hostile attacks. 
Marx and Engels also conducted an intensive and sometimes controversial discussion on the world political events of their day—the American Civil War, the Crimean War, the Polish uprising of 1863, and many other developments. They wrote about these issues in international publications. Engels sometimes relieved Marx of the work and wrote articles that then appeared in Marx’s name.
They became politically active once again as soon as circumstances permitted. After a period of reaction in the 1850s, the workers’ movement grew strongly from the beginning of the 1860s. In 1864, the First International, the International Workingmen’s Association, was founded, with Marx as its guiding spirit. It was the first attempt to build the workers’ movement on a unified, socialist perspective, and it demanded a considerable portion of Marx’s time.
Despite the time taken up by his professional, journalistic and political activities in Manchester, Engels found time to continue his education. He expanded and deepened his knowledge of languages. He emerged as a military scientist who garnered respect in bourgeois circles, which secured him the nickname “General,” and he closely followed the latest developments in the natural sciences.
Engels’ role after Marx’s death
Karl Marx died on March 14, 1883. Engels survived him by 12 years. During this time, he not only completed the second and third volumes of Capital, but also made a decisive and creative contribution to the further development of Marxism and played a leading role in the development of the international socialist workers movement, which grew rapidly.
Already in the 1870s, as Marx’s creative abilities declined significantly due to increasing ill health, Engels’ contribution to their joint work grew on the theoretical, political and organisational fronts. If Marx played the “first violin” in the working out of the historical materialist world outlook, Engels took over this role in the building of new mass working class parties, which brought with it new challenges.
Following his return from Manchester, Engels quickly became a member of the International Workingmen’s Association’s General Council. He was the corresponding secretary for Belgium, Italy and Spain. Engels and Marx, who both spoke Russian, also focused on Russia.
The International Workingmen’s Association was plunged into crisis following the German-French war and the defeat of the Paris Commune in 1871, and was ultimately dissolved. But the socialist workers’ movement soon began to grow rapidly again. On July 14, 1889, the 100th anniversary of the French Revolution, the Second International was founded in Paris at Engels’ initiative. Around 300 parties and organisations from 20 countries were represented. Engels was in particularly close contact with the leaders of the German Social Democracy, who regularly sought his advice.
Karl Kautsky described the prominent role played by Marx and Engels in the First International, and by Engels in the Second International:
Little wonder that the intelligent socialist element of all countries went for advice to the two veterans in London whenever they found themselves in a critical situation. And never were those who went disappointed. They spoke out their convictions freely and frankly without circumlocution, but also without obtrusiveness. No proletarian, no one to whom the subject of the proletariat was a serious matter, went to these two in vain. That they were the advisers of the whole fighting proletariat of Europe and America, pamphlets, numerous articles and numberless letters, in different languages, bear evidence. 
The incredible volume of correspondence maintained by Engels can be gauged by the Marx Engels Gesamtausgabe, a complete edition of their works, which is still in progress. Marx and Engels’ entire correspondence fills 35 volumes, each of which is between 1,300 and 1,500 pages long, with 13 of them appearing so far in print. The correspondence following Marx’s death, which Engels maintained himself, alone encompasses 10 volumes.
Along with the international political work, the management of Marx’s literary estate, and the completion of the two final volumes of Capital—each of which would have required the labour of many people—Engels authored a number of significant works that secured the triumph of Marxism as the theoretical and political basis of the world socialist movement. They were printed in large numbers, translated into numerous languages, and made Marxism accessible to hundreds of thousands of workers around the world.
Engels’ masterful command of language, his ability to present complex material in an understandable way, his encyclopedic knowledge, and his humour, which shone through even in connection with the most serious topics, make the reading of his works a pleasure to this day. This applies not only to the Marxist classics, but also to his contemporary articles and contributions. In these he demonstrated a degree of political acuteness and farsightedness that, apart from Marx, perhaps only Leon Trotsky possessed.
For example, in December 1887, when the capitalist economy was seemingly on an unstoppable upward trajectory and the first reformist illusions made themselves felt in Social Democracy, Engels predicted with remarkable precision the outbreak of a world war. In the foreword to an anti-militarist pamphlet, he warned:
No war is any longer possible for Prussia-Germany except a world war and a world war indeed of an extent and violence hitherto undreamt of. Eight to ten millions of soldiers will massacre one another and in doing so devour the whole of Europe until they have stripped it barer than any swarm of locusts has ever done. The devastations of the Thirty Years’ War compressed into three or four years, and spread over the whole Continent; famine, pestilence, general demoralisation both of the armies and of the mass of the people produced by acute distress; hopeless confusion of our artificial machinery in trade, industry and credit, ending in general bankruptcy; collapse of the old states and their traditional state wisdom to such an extent that crowns will roll by dozens on the pavement and there will be nobody to pick them up; absolute impossibility of foreseeing how it will all end and who will come out of the struggle as victor; only one result is absolutely certain: general exhaustion and the establishment of the conditions for the ultimate victory of the working class. 
These lines alone make clear how absurd the claim is that, confronted with the organisational successes of the Social Democrats, Engels was transformed into a reformist at the end of his life.
While Marx was still alive—and in close collaboration with him—Engels published a series of fundamental theoretical writings. They not only presented the jointly worked out world outlook in a systematic and coherent manner, but also further developed it. Engels’ extensive knowledge, in particular, of the natural sciences, which made tremendous progress during the 19th century, played a crucial role. Like Lenin after him, Engels understood that materialist philosophy cannot be defended and further developed if it does not constantly take into account the latest advances in the natural sciences.
Between 1877 and 1878, Herr Eugen Dühring’s Revolution in Science was published, initially as a series of articles in the German Social Democratic Party’s central organ Vorwärts. First conceived of as a polemic against the theoretical charlatan and subsequent founder of racist anti-Semitism, Eugen Dühring, whose proclamation of a “system” of ultimate truths created great confusion in the SPD, Anti-Dühring soon developed into a comprehensive elaboration of the Marxist standpoint in philosophy, natural science and the social sciences. Engels wrote” “(M)y negative criticism became positive, the polemic was transformed into a more or less connected exposition of the dialectical method and of the communist world outlook championed by Marx and myself—an exposition covering a fairly comprehensive range of subjects.” 
Anti-Dühring, which presents all of the views on the dialectics of nature and on historical and dialectical materialism that Engels would deepen in future works, emerged in the closest collaboration with Marx. “I read the whole manuscript to him before it was printed, and the tenth chapter of the part on economics (“From Kritische Geschichte”) was written by Marx,” noted Engels.  Subsequent accusations that Anti-Dühring represented a “positivist” vulgarisation of Marx’s views are thus conjured up out of thin air.
On the basis of Anti-Dühring, Engels published Socialism: Utopian and Scientific, an introduction to socialism for which Marx wrote a foreword. It was published in countless editions in a large number of languages.
Key chapters in Dialectics of Nature, a work that remained incomplete and appeared only after Engels’ death, were also already developed during the 1870s. Engels demonstrated in detail that the dialectic is not confined to thought. Nature, he wrote, is “the proof of dialectics,” which “comprehends things and their representations, ideas, in their essential connection, concatenation, motion, origin and ending.” “Modern natural science,” he continued, “has furnished this proof with very rich materials increasing daily, and thus has shown that, in the last resort, Nature works dialectically and not metaphysically.” 
Following Marx’s death, Engels published a series of important works that theoretically deepened their common world outlook. The Origins of the Family, Private Property, and the State, which drew on recent research to trace the role of the state, property and family in earlier cultural phases and thus historically relativised them, was published in 1884. The work had a major influence on Lenin’s The State and Revolution, which he wrote on the eve of the October Revolution.
Ludwig Feuerbach and the End of Classical German Philosophy (1888) is an ingenious summary of the history of philosophy, whose division of the philosophers into two great camps—idealists, “(t)hose who asserted the primacy of spirit to nature and, therefore, in the last instance, assumed world creation in some form or other,” and materialists, “who regarded nature as primary”—provides to this day the key to an understanding and categorisation of the different philosophical schools.
Alongside these fundamental theoretical works, Engels authored numerous works on the history of the Marxist movement (Marx and the Neue Rheinische Zeitung, On the History of the Communist League), biographical sketches (on the poet Georg Weerth and the workers’ leader Johann Philipp Becker), important forewords to new editions of Marxist writings, and statements on contemporary political issues.
Engels died in London on Aug. 5, 1895, at the age of 74.
The attempt to play Engels off against Marx
For a long period, it was taken for granted that Marx and Engels, in the words of Marx’s daughter, Eleanor, were “so closely associated that they cannot be separated.” But over the past six decades, an out-and-out competition has developed within academic circles to separate the two.
Common to all of these attempts is the accusation that Engels is guilty of a “positivist vulgarisation” of Marx. Through his identification of Marxism with materialism, he turned against the philosophical humanism that Marx had propounded in his early writings, it was claimed. Moreover, while for Marx the dialectic was manifest only in the interplay between social practice and human thought, Engels falsely rooted the dialectic in matter and nature.
These claims can be easily refuted. Marx and Engels’ lifelong collaboration, as well as the fact that Engels developed his understanding of the dialectic of nature and materialism, as we have shown, in close consultation with Marx, disprove them. However, Engels’ opponents are not concerned with historical facts. The attack on Engels and materialism is an attempt to separate “Marxism” from the working class and the building of a revolutionary party for the overthrow of capitalism.
Georg Lukacs and Karl Korsch advanced such standpoints as early as the 1920s. The Frankfurt School then pushed them to their limit. In their major work Dialectic of Enlightenment, published after the Second World War, Max Horkheimer and Theodor Adorno explicitly rejected the historical materialist understanding of society, and with it, the revolutionary role of the working class.
They stated that the progress of the productive forces does not initiate an epoch of social revolution, or form the basis for a higher, socialist form of society. Rather, it leads to the dulling of the masses, a cultural decline, and ultimately the relapse of society into barbarism.
They wrote, “The curse of irresistible progress is irresistible regression… The powerlessness of the workers is not merely a ruse of the rulers, but the logical consequence of industrial society...” 
The Frankfurt School, as David North wrote, “sought to convert Marxism from a theoretical and political weapon of proletarian class struggle, which Horkheimer, Adorno and Marcuse rejected, into a socially amorphous form of cultural criticism, in which the political pessimism, social alienation, and personal and psychological frustrations of sections of the middle class found expression.” 
During the 1960s, as the working class and youth were radicalised around the world, the attacks on Engels were intensified. In 1961, George Lichtheim published his influential book Marxism: An Historical and Critical Study. It portrayed Engels as a one-dimensional determinist and positivist, while Marx in his writings between 1843 and 1848 had developed a “complex dialectic of existence and essence, reality and ‘alienation.’” 
One year later, the book The Concept of Nature in the Teaching of Marx was published by Alfred Schmidt, a pupil of Adorno and Jürgen Habermas, which advocated similar theses. These anti-Marxist polemics played an important role in separating the youth protest movements from the working class. Over the ensuing years, these positions gained the upper hand within “left” academic circles, and were combined with the reactionary and irrationalist conceptions of post-modernism.
Lichtheim claimed that a direct line led from Engels through Kautsky, Plekhanov and Lenin to the Stalinist dictatorship in the Soviet Union. They all had, irrespective of their differences, a “common faith in ‘dialectical materialism’ as a universal ‘science,’” which “became the cornerstone of the Soviet Marxist edifice.” 
The absurdity of this argument is obvious. First, the Stalinist dictatorship was not based on Marxism, but on the suppression and murder of tens of thousands of revolutionary Marxists, which culminated in the Great Terror of 1937–38. Second, the Marxists of the Trotskyist Left Opposition were the only ones who correctly appraised Stalinism beginning in 1923 and predicted its development. Third, as in the economic field, Stalinism lived a purely parasitic existence in the ideological field.
The Stalinist bureaucracy was, as Trotsky repeatedly stressed, not a class. It usurped power in the workers’ state and lived off the property relations created by the October Revolution. The same was true of Marxist ideology. The fact that the rulers erected statues of Marx and Engels, named streets and cities after them, published their books, and declared “diamat” to be a compulsory school subject, did not mean that they based themselves on Marxism. It merely shows that even the most revolutionary theory can be perverted when an authoritarian state apparatus stands behind it. Anyone who dared to criticise the Stalinist regime on the basis of the writings of Marx and Engels was pursued by the secret police and state prosecutors, and ended up in prison, in a labour camp or in front of a firing squad.
The attacks on Engels and historical materialism continued after the dissolution of the Soviet Union. In his essay “Hegel, Marx, Engels, and the origins of Marxism,” David North has presented a detailed refutation of philosophy professor Tom Rockmore, whose 2002 book Marx after Marxism sought to revive the attacks on Engels. North wrote,
What Rockmore advocates—a Marx without historical materialism, without Engels, without Marxism—proves in the end to be a Marx without socialist revolution, a “Marx” that is not simply stood on his head, but also handcuffed and gagged. 
One cannot conclude a retrospective on Friedrich Engels without examining his extraordinary human qualities. As far as personal integrity, courage and the striving for the cause of human liberation are concerned, he is among the most noble figures in world history. There are countless witnesses to testify to his graciousness, his charm, his indestructible optimism, his love of life, and his unbreakable loyalty to his friend Marx. One of the best came from the pen of Leon Trotsky:
Engels’ relations with people were foreign to all sentimentalism or illusions and permeated through and through with a penetrating simplicity and, therefore, profoundly human. In his company around the evening table, where representatives of various countries and continents gathered, all contrast disappeared as if by magic between the polished radical duchess Schack and the not at all polished Russian Nihilist, Vera Zasulich. The rich personality of the host manifested itself in this happy capacity to lift himself and others above everything secondary and superficial, without departing in the least either from his views or even his habits. 
And yet, according to Trotsky, nothing human was foreign to Engels:
The man of duty and of profound attachments bears the least resemblance to an ascetic. He was a lover of nature and of art in all its forms, he loved the company of clever and merry people, the presence of women, jokes, laughter, good dinners, good wine and good tobacco. At times he was not averse to the belly-laughter of Rabelais who readily looked for his inspiration below the navel. 
Wilhelm Liebknecht, a veteran of the 1848 revolution who joined the Communist League, worked closely with Marx and Engels in England for many years, and founded German Social Democracy together with August Bebel, said at Engels’ grave:
He was a wonderfully multifaceted and at the same time fully self-contained personality, a personality in great and small things—capable of the greatest and never neglectful of the smallest. Selfless, always subordinating himself to the cause, until Marx’s death and even thereafter sacrificing his person for his great friend, he always led a life of duty, always setting the highest standards for himself… Nothing human was foreign to him, he met his obligations always and everywhere, and was tender and serene—serene even in the most serious struggles. 
Two hundred years after Engels’ birth, his theoretical and political legacy is more relevant than ever before. The International Committee of the Fourth International, which has defended and developed this heritage, is becoming a point of attraction for all who are searching for a revolutionary socialist alternative to bankrupt capitalism.
 Karl Marx & Frederick Engels, Collected Works [MECW], “Karl Marx’s Funeral,” Volume 24, p. 468.
 Leon Trotsky on Engels and Kautsky, Mehring Books, 2020, pp. 13–18.
 Ibid., pp. 9–10.
 Ibid., p. 8.
 Vladimir Lenin, Collected Works, “Frederick Engels,” Volume 2, p. 24.
 MECW, “The German Ideology,” Volume 5, p. 30.
 Ibid., p. 53–54.
 MECW, “Revolution and Counter-Revolution in Germany,” Volume 11, p. 40.
 MECW, “Address of the Central Authority to the League,” Volume 10, pp. 280, 287.
 Leon Trotsky on Engels and Kautsky, Mehring Books, 2020, pp. 11–12.
 Karl Kautsky, „Friedrich Engels. Zu seinem siebzigsten Geburtstag“. In: Die Neue Zeit, 9. Jahrg., 1. Bd., 1890/1891 [Karl Kautsky, “Friedrich Engels. On His Seventieth Birthday.” In: Die Neue Zeit (New Times), Ninth Year, First Volume, 1890/1891].
 MECW, “Introduction [To Sigismund Borkheim’s Pamphlet, In Memory of the German Blood-and-Thunder Patriots. 1806–1807], Volume 26, p. 451.
 MECW, Anti-Dühring, Preface from 1885, Volume 25, p. 8.
 Ibid., p. 9.
 MECW, Socialism: Utopian and Scientific, Volume 24, p. 301.
 Max Horkheimer & Theodor Adorno, Dialectic of Enlightenment, Stanford University Press, 2002, p. 28.
 David North, The Frankfurt School, Postmodernism and the Politics of the Pseudo-Left. A Marxist Critique, Mehring Books, 2016, p. 134.
 George Lichtheim, Marxism: An Historical and Critical Study, New York, 1961, pp. 58–59.
 Ibid., pp. 234–35.
 David North, “It was all Engels’ Fault: A Review of Tom Rockmore’s Marx After Marxism,” in: David North, The Russian Revolution and the Unfinished Twentieth Century, Mehring Books, 2014, p. 360.
 Leon Trotsky on Engels and Kautsky, Mehring Books, 2020, p. 9.
 Wilhelm Liebknecht, „Zum Tod von Friedrich Engels“, 10. August 1895 (online) [Wilhelm Liebknecht, “On the Death of Friedrich Engels,” 10 August 1895].