This collection of documents, sealed for years in Stalin's secret archives, gathers some of Karl Bernhardovich Radek's most important contributions to the early Soviet debates about China and its working-class. Radek (1885-1939) was the foremost Soviet specialist on China, a leading activist in the Russian revolutionary movement, and a leader of the Trotskyist Opposition. In these letters, articles, and minutes he presents an original conception of the history of China from ancient times to the twentieth century, as well as a delineation of the fundamental political problems of China in the 1920s. The appendices also contain communications between Trotsky and Radek, as well as the "Chronological Information" of Zionviev and Trotsky, outlining the most important stages of the struggle of the United Left Opposition against the Stalinist majority in the All-Union Commuist Party regarding problems of the first Chinese revolution. None of the documents collected here have ever been published in English.