Friedrich Engels

Friedrich Engels (German: [ˈfʁiːdʁɪç ˈɛŋl̩s]; 28 November 1820 – 5 August 1895) was a German philosopher, social and political theorist, journalist, businessman, and revolutionary socialist. He is best known for his lifelong collaboration with Karl Marx, with whom he co-authored The Communist Manifesto (1848) and developed the political and philosophical system that came to be known as Marxism. After Marx's death, Engels served as the editor of his works, completing the second and third volumes of Das Kapital.
Born in Barmen, Prussia, to a prosperous mercantile family, Engels rejected his family's devoutly pietistic values from a young age. He became involved with the Young Hegelians while performing military service in Berlin and embraced a materialist philosophy. In 1842, his father sent him to Manchester, England, to work in a cotton mill in which the family had an investment. His experiences of the industrial working class there led him to write his first major work, The Condition of the Working Class in England (1845).
In 1844, Engels began a permanent partnership with Marx in Paris. Together they worked to critique the prevailing idealist philosophies and develop their materialist conception of history, notably in The Holy Family (1845) and The German Ideology (unpublished in their lifetimes). They became active in the Communist League, which commissioned them to write the Manifesto.