Sean McDermott and James Connolly were the last to be executed by Maxwell on 12 May 1916. Both were signatories of the proclamation.
It was Sean MacDiarmada that read Padraig Pearse's letter of surrender to those in the G.P.O. Sean "limped his way to the Stonebreakers Yard. The time was 3:45 a.m." (Rebels: The Irish Rising of 1916 by Peter De Rosa pg. 502)
Connolly was severely wounded and had to be transported to the execution on a stretcher. They also had to prop him up in a chair in order to execute him. "Connolly was the only one of the ring leaders not to be jailed at Kilmainham." (Rebels: The Irish Rising of 1916 by Peter De Rosa pg. 502)