It was surrendered when it was taken by British troops on the morning of Tuesday 25 April. He was interned until December 1916 in Frongoch. During the Civil war in Ireland George was quartermaster for the Irish Citizen Army. He also fought for the Anti-Treaty forces in Dublin in 1922. He used his home as an arms dump for the Irish Citizen Army and the IRA until a raid in February 1925. He was arrested and imprisoned again as a result.