George Gilmore was a Protestant Irish Republican Army leader during the 1920s and 1930s. During his period of influence the Republican movement moved significantly to the left. After leaving the movement in 1934 he remained a significant figure on the Irish left.
Born in Portadown

Portadown

Portadown is a town in County Armagh, Northern Ireland. The town sits on the River Bann in the north of the county, about 23 miles south-west of Belfast...

, Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

, he led the South County Dublin Battalion of the IRA from 1915 to 1926.
He fought in the IRA in the Irish War of Independence

Irish War of Independence

The Irish War of Independence , Anglo-Irish War, Black and Tan War, or Tan War was a guerrilla war mounted by the Irish Republican Army against the British government and its forces in Ireland. It began in January 1919, following the Irish Republic's declaration of independence. Both sides agreed...

 and in the Irish Civil War

Irish Civil War

The Irish Civil War was a conflict that accompanied the establishment of the Irish Free State as an entity independent from the United Kingdom within the British Empire....

 on the Anti-Treaty IRA side.