One of the lesser-known contributions of Marx and Engels can be found in their extensive journalistic writings on the United States’ Civil War (1861-1865). In their writings and their solidarity activity in the UK, Marx and Engels’ offered a historical materialist analysis and working class perspective on the war. The civil war fought between the industrialised Union in the North and the Confederacy in the South would determine the preservation or abolition of slavery. Today however, some academic currents reject the centrality of the abolition of slavery to the war. Was the US civil war a “revolutionary” struggle? How do Marxists understand the motivations of the Northern elite? This talk will consider Marx’s writings and political intervention, and its lessons for today.