Friedrich Engels was a German philosopher, social and political theorist, 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. November 28, 1820 – August 5, 1895; died at 74. Alive at the same time as Albert Einstein, Abraham Lincoln, Leo Tolstoy, Vincent van Gogh, and Frédéric Chopin. Wiki link