James Moroka had gone to school in Edinburgh and had become a well sought after doctor in Thaba Nchu where he had his own practice, with a both Black and White clientele list. In 1935 he attended his first All African Convention (AAC) meeting, and in 1936 he became the treasure of the AAC and was a member of the 1936 AAC delegation to the government to convey African feeling towards the drafted bills. In 1943, Moroka became a member of the ANC’s Atlantic Charter Committee and helped to draft a Bill of Rights. In 1949 he became the president-general of the ANC, during a time when the ANC had started to implement more armed tactics against Apartheid.
During Moroka's three-year presidency, the ANC was dominated by radical members of the Youth League and the ANC became a more militant organization. The Defiance Campaign had been launched during Moroka's reign on April 6, 1952. And on July 30th, 1952, 21 leaders of the ANC, including Moroka, were arrested under the Suppression of Communism Act. This ended Moroka's reign of leadership, and in December of 1952 Albert Luthuli succeeded James Moroka.