William James Greer was born at Mawillian, Cookstown. He enlisted in Belfast, with the 10th Battalion Royal Irish Rifles. This Battalion was raised in Belfast from the Belfast Volunteers and did much of their training at Newcastle, Ballykinlar and Seaford. They landed at Boulogne in October 1915. Their training continued until just prior to the start of the Somme offensive. William James was killed on the first day of the battle as he tried to cross No Mans Land

The Thiepval Memorial will be found on the D73, next to the village of Thiepval, off the main Bapaume to Albert road (D929). Each year a major ceremony is held at the memorial on 1 July.