A champagne-loving industrialist who enjoyed hunting, a literary critic and an upstanding Victorian gentleman: this does not sound like a description of your typical advocate of proletarian revolution or the co-author of the Communist Manifesto. Yet Friedrich Engels was all those things and more. Deliberately keeping in the shadows of his comrade-in-arms Karl Marx, Engels led an eventful life, fighting in the 1848 German revolution, attending secret meetings with Chartists and keeping two homes in Manchester: a respectable one that fitted his image of a bachelor businessman, the other a boarding house where he lived with his working-class lover Mary Burns and her sister, and future wife, Lizzie.

Photo: Statues of Karl Marx and Friedrich Engels in Berlin. (Getty Images)