[6] He was a member of the Irish Volunteers and on the outbreak of the 1916 Easter Rising, he cycled the 26 kilometres to Dublin, found the Rising was on and returned to Maynooth, where he gathered his men, marched them to Dublin and fought in the GPO and as a sniper in outposts in the Exchange Hotel in Parliament Street and Arnott's Henry Street; he was a crack shot.

He made it to the Broadstone railway station but was held there by British soldiers and sent to Richmond Barracks and from there to Knutsford Prison and then Frongoch internment camp in Wales.

[10] He was chosen by Éamon de Valera to become Governor-General of the Irish Free State following James McNeill's resignation in November 1932.

While he continued to give royal assent to legislation, summon and dissolve Dáil Éireann and fulfil the other formal duties of the office, he declined all public invitations and kept himself invisible, as advised by his Government.

In fact in his period in office he performed only one public function: the receipt of the credentials of the French Ambassador to Ireland in the Council Chamber, Government Buildings, 1933, on behalf of King George V. However, de Valera subsequently had that duty moved from the Governor-General to his own post of President of the Executive Council; instead of presenting his credentials to Ua Buachalla, the US Legation Minister, William Wallace McDowell, presented himself to de Valera.

De Valera sought to use the abdication crisis surrounding King Edward VIII to amend the Irish Free State's Constitution to abolish both the Crown and the office of governor-general.

Having done so, he faced a threat of a court case from Ua Buachalla, who had been left personally liable for the remaining one year's expensive private lease on his residence, following the sudden abolition of his office.

Ua Buachalla had, in 1932, on de Valera's explicit advice, leased the residence for a full five years, which was his expected term of office.

Eventually, de Valera was forced to grant Ua Buachalla a large pension and to pay his outstanding rent and expenses to stop a potentially embarrassing court case going ahead.