Seán Heuston Seán Heuston , ( 21 February 1891 – 8 May 1916 ) , born Jack Heuston , and sometimes referred to as J . J . Heuston , was an Irish rebel and member of Fianna Éireann who took part in the Easter Rising of 1916 . With about 20 Volunteers , he held the Mendicity Institution on the River Liffey for over two days , though it was originally only intended to be held for 3 – 4 hours . He was executed by firing squad on 8 May in Kilmainham Gaol . Early life . Heuston was born in Dublin on 21 February 1891 and educated by the Christian Brothers . He worked as a railway clerk in Limerick and while there took an active part in Fianna Éireann , of which he was an officer . Seán Heuston arranged for members who could not afford to buy their uniforms to do so by paying small weekly sums . Under his guidance the Fianna in Limerick had a course which encompass not only drilling , which was made up of signalling , scout training and weapons training but also lectures on Irish history and Gaelic classes . Irish Volunteers . In 1913 Heuston was transferred to Dublin Fianna , and was appointed to the Emmet Sluagh . He went on to join the ranks of the Irish Volunteers and played a prominent part in the Easter Rising . Easter Rising . Heuston was the Officer commanding of the Volunteers in the Mendicity Institution ( now called Heuston ' s Fort ) on the south side of Dublin city . Acting under Orders from James Connolly , Heuston was to hold this position for three or four hours , to delay the advance of British troops . This delay was necessary to give the headquarters staff time to prepare their defences . Having successfully held the position for the specified period , he was to go on to hold it for over two days , with twenty - six Volunteers . With his position becoming untenable against considerable numbers , and the building almost completely surrounded , he sent a dispatch to Connolly informing him of their position . The dispatch was carried by two Volunteers , P . J . Stephenson and Seán McLaughlin , who had to avoid both sniper fire and British troops across the city . It was soon after sending this dispatch that Heuston decided to surrender . The Surrender . Séamus Brennan , a member of the Mendicity Institution Garrison under Heuston , gave the following account of the decision to surrender : Prisoners . According to the statement given by Séamus Brennan to Piaras F . Mac Lochlainn , author of " Last Words " , the British troops were " infuriated when they saw the pygmy force that had given them such a stiff battle and caused them so many casualties " . Séamus Brennan never saw Seán Heuston again after being transferred to Arbour Hill Detention Barracks . Court Martial . Heuston had been transferred to Richmond Barracks , and on 4 May 1916 , he was tried by Court Martial . On the Sunday , 7 May 1916 , the verdict of the Court Martial was communicated to him that he had been sentenced to death and was to be shot at dawn the following morning . Execution . Prior to his execution he was attended by Father Albert , O . F . M . Cap in his final hours . Father Albert wrote an account of those hours up to and including the execution : Father Albert concluded : References . city