Rory O'Connor was an active participant in both the War of Independence and the Civil War. He produced the 'Castle order' showing plans for strong actions by the authorities against nationalist organisations. During the Easter Week Rebellion in 1916 he fought and was wounded. Became the Director of Engineering with the IRA in 1918 and directed operations in England including the Manchester Jail rescue in 1919 and the burnings in Liverpool in 1920. During the Civil War he was a signatory to the Anti-Treaty declaration (June 1922) and a prominent member of the Four Courts garrison. After surrendering, he was imprisoned in Mountjoy. In 1922 he was executed as a reprisal for the shooting of Se·n Hales.