Moissaye Joseph Olgin (24 March 1878 – 22 November 1939) was a Ukrainian-born writer, journalist, and translator in the early 20th century. He began his career writing for the Jewish press in support of the Russian Revolution in 1910. During the First World War, he moved to the United States in 1915, settling in New York City, where he continued his career in journalism. Much of his work was in support of communism, and he was a founding member of the Workers Party. In 1922, he founded The Morning Freiheit, and served as its editor until his death in 1939.