James J. "Jim" Oneal (March 13, 1875 – December 12, 1962), a founding member of the Socialist Party of America (SPA), was a prominent socialist journalist, historian, and party activist who played a decisive role in the bitter party splits of 1919–21 and 1934–36.
Oneal was born March 13, 1875 in Indianapolis, Indiana, the son of an iron worker. Upon the death of his father, Oneal was forced to leave school to go to work in a steel mill to help support his family. Oneal attended public school only to the 6th grade, relying instead upon self-education.
Oneal was an early convert to social democratic politics, joining the Socialist Labor Party of America in 1895 before leaving to join the Chicago-based Social Democratic Party of America (SDP) of Victor L. Berger and Eugene V. Debs shortly after its founding in 1897. Long a resident of Terre Haute, Indiana, Oneal was a close personal friend of his neighbor Debs.
Oneal was a delegate to the 1900 convention of the SDP and to the 1901 Unity Convention at which the Socialist Party of America (SPA) was born. He was also elected as the first State Secretary of the Socialist Party of Indiana, state affiliate of the SPA, shortly after establishment of the new party. The following year Oneal was elected to the governing National Committee of the SPA as the representative of the Socialist Party of Indiana.
In 1903, Oneal moved to Omaha and went to work in the party's National Office as an assistant to Executive Secretary William Mailly. He continued in that role until 1905, at which time he left to become the Associate Editor of the New York Worker, forerunner of the great Socialist daily, the New York Call. After leaving the Worker in 1908, Oneal returned home to Indiana, where he was elected the State Secretary of the SP of Indiana from 1911 to 1913. By 1915, Oneal had relocated again, this time to Massachusetts, where he was elected State Secretary of that party in 1915, continuing in that post until 1917.