Arthur Rosenberg was one of the most remarkable Marxist historians of the twentieth century, yet he remains largely unknown in the English-speaking world. Rosenberg began his intellectual career as a historian of the ancient world before he was radicalized by the experience of World War One and became an activist on Germany’s radical left, joining the Communist Party of Germany (KPD) and representing the party in the Reichstag.

After playing a significant role in the KPD leadership for much of the 1920s, Rosenberg left the party but retained his Marxist convictions, which he now brought to bear on his work as a historian. Rosenberg wrote important books on modern German history and composed a major analysis of fascism that still stands out for its prescience almost ninety years later. Although he died in relative obscurity as an impoverished exile from Nazism in the United States, Rosenberg left behind a brilliant intellectual legacy that can still inform the work of socialists today.