May 9 - Hopes of finding Sir Hugh Lane alive have faded completely. He was a patron of Irish painting and modern art, and was one of many people who were on board the Luisitania.
May 25 - The British Prime Minister appoints a national wartime coalition of 12 Liberals, 8 Unionists and 1 Labour member. In Dublin the Irish Parliamentary Party approves John Redmond's decision not to join.