Jose Carlos Mariategui is one of Latin America s most profound but overlooked thinkers. A self-taught journalist, social scientist, and activist from Peru, he was the first to emphasize that those fighting for the revolutionary transformation of society must adapt classical Marxist theory to the particular conditions of Latin American. He also stressed that indigenous peoples must take an active, if not leading, role in any revolutionary struggle.

Today Latin America is the scene of great social upheaval. More progressive governments are in power than ever before, and grassroots...