Karl Marx was a German-born scientist, philosopher, economist, sociologist, journalist, and revolutionary socialist. Born in Trier to a middle-class family, he later studied political economy and Hegelian philosophy. As an adult, Marx became stateless and spent much of his life in London, England, where he continued to develop his thought in collaboration with German thinker Friedrich Engels and published various works, the most well-known being the 1848 pamphlet The Communist Manifesto. His work has since influenced subsequent intellectual, economic, and political history.