[3] Robinson served as monk in Scotland in his early adulthood until he got permission in 1913 from the abbot to leave the monastery and participate in the Irish independence movement.

On Easter Monday, he marched his section to Sackville Street and was greeted by Peadar Bracken who showed him an order from Commandant James Connolly which directed him to seize Hopkins and Hopkins jeweller's on the corner of Sackville Street.

[5] He held this position under constant fire until Thursday where he directed his section across the road to the General Post Office.

These four men were referred to as 'the big four' and were keenly sought by the Royal Irish Constabulary (RIC) and the British military.

A thousand-pound reward was offered for information leading to their capture, this was later raised to ten thousand pounds.

The Police Gazette, ‘The Hue and Cry' regularly published accurate descriptions of the wanted men.

On 23 February 1919 at a Brigade meeting in Nodstown Tipperary, Robinson and other Brigade officers drafted a proclamation (signed by Robinson) ordering all British military and police forces out of South Tipperary and, if they stayed they would be held to have "forfeited their lives".

Robinson and Seán Treacy travelled to Dublin and met Michael Collins and told him that they, Hogan and Breen would remain in Ireland.

On 19 December 1919, a group of eleven IRA men, including Treacy, Robinson, Hogan, Paddy Daly, Joe Leonard, Martin Savage and Breen attempted the assassination of the Lord Lieutenant of Ireland, Lord French.

When the Irish Civil War broke out over the Treaty, Robinson sent some of his Tipperary men to help the anti-Treaty IRA fighters in Dublin, after a plea from Oscar Traynor.