The leading cultural activist in the Canadian Communist Party in the 1930s, Oscar Ryan was the formative figure in the Workers’ Theatre movement in Canada and a tireless advocate of revolutionary theatrical modernism. Born Oscar Weinstein, he took his underground name from his mother’s maiden name, Rein. He grew up in Montreal and Winnipeg and after high school joined the Young Communist League as a full-time party activist. With an idiomatic and forceful proletarian writing style in the manner of John Dos Passos and Mike Gold, he became a writer for the Communist Party’s Daily Worker and its successors, the Daily Clarion and the Canadian Tribune. As Martin Stone, he was a theater critic for the Tribune from 1955 to 1988. In the Communist Party of Canada, he was an early supporter of Tim Buck, who took over the party in 1929 when communist parties around the world assumed a more radical militant stance in answer to Stalin’s call for revolutionary class war. Under Buck, Ryan became a leading figure in the party’s propaganda wing, a cultural organizer, publicity director of the Canadian Labour Defence League, and the author of numerous pamphlets.