N'afọ 1848, Engels so Marx dee The Communist Manifesto, ya na ya mekwara ọtụtụ akwụkwọ ndị ọzọ. Mgbe nke ahụ gasịrị, Engels kwadoro Marx n'ụzọ ego, na-enye ya ohere ime nnyocha na ide Das Kapital. Mgbe Marx nwụsịrị, Engels dezigharịrị mpịakọta nke abụọ na nke atọ nke Das Kapital. Na mgbakwunye, Engels haziri ndetu Marx na Theories of Surplus Value, nke o mechara bipụta dị ka "mpịakọta nke anọ" nke Capital. N'afọ 1884, ọ bipụtara Mmalite nke Ezinụlọ, Ihe Onwunwe nke Onwe na Steeti dabere na ajụjụ agbụrụ nke Marx.
Engels