Easter Rising in putting the rising off for only a day, although it greatly reduced the number of Volunteers who turned out. British Naval Intelligence had been aware of the arms shipment, Casement's return, and the Easter date for the rising through radio messages between Germany and its embassy in the United States that were intercepted by the Royal Navy and deciphered in Room 40 of the Admiralty. The information was passed to the Under-Secretary for Ireland, Sir Matthew Nathan, on 17 April, but without revealing its source, and Nathan was doubtful about its accuracy. When news reached Dublin of the capture
Michael Collins (Irish leader) to his appointment as financial advisor to Count Plunkett, father of one of the Easter Rising's organisers, Joseph Plunkett. Collins took part in preparing arms and drilling troops for the insurrection. The Rising was Collins' first appearance in national events. When it commenced on Easter Monday 1916, Collins served as Joseph Plunkett's aide-de-camp at the rebellion's headquarters in the General Post Office (GPO) in Dublin. There he fought alongside Patrick Pearse, James Connolly, and other members of the Rising leadership. The Rising was put down after six days, but the insurgents achieved their goal of holding their positions for the