John Louis Engdahl was an American socialist journalist and newspaper editor. One of the leading journalists of the Socialist Party of America, Engdahl joined the Communist movement in 1921 and continued to employ his talents in that organization as the first editor of The Daily Worker. Engdahl was also a key leader of the International Red Aid (MOPR) organization based in Moscow, where he died in 1932.

Adoph F. Germer was an American socialist political functionary and union organizer. He is best remembered as National Executive Secretary of the Socialist Party of America from 1916 to 1919. It was during this period that the Left Wing Section of the Socialist Party emerged as an organized faction. Germer was instrumental as one of the leaders of the SPA's "Regular" faction in orchestrating a series of suspensions, expulsions, and "reorganizations" of various Left Wing states, branches, and locals and thereby controlling the pivotal 1919 Emergency National Convention of the SPA, and thus forcing the Left Wing to establish new organizations of their own, the Communist Labor Party of America and the Communist Party of America.