Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
He was the son of Peter and Elizabeth Dwyer.

Source: Leicestershire War Memorials Project.
William was part Irish, his father Patrick Peter Dwyer having been born in Clonmel, County Tipperary. His mother Annie died giving birth. Patrick was a groom and moved around the country seeking good positions. After re-marrying a Skegness girl, some eleven years younger than him in 1897, Patrick found work in East Norton and then as a coachman in Hallaton. After leaving Hallaton school, young William worked as a domestic gardener. He was called to the colours sometime between September 1915 and February 1916 and enlisted in the East Yorkshire Regiment with army service number 31126. His military records were burnt in World War II so we have no information about his service. On 15th September 1916, the Battalion was part of an attack in the Battle of Flers-Courcelette, one of the phases of the Battle of the Somme and where tanks were used for the first time. As a measure of their fundamental unreliability, 17 tanks were unable to make it as far as the front line. Of the 22 that did, a further 7 failed to work at zero hour. Thus 15 of the 49 tanks rolled slowly into No Man's Land with the start of the attack on 15 September. But the impact of German morale was powerful. The fighting was a confused affair, with company’s finding themselves isolated and our own guns firing on our men. The Germans counterattacked strongly and eventually after some modest gains the attack was called off on 22nd September. But William Dwyer did not survive. He was killed on 16th September and his body was never recovered. He is commemorated on Hallaton War memorial and also on the Thiepval Memorial to the Missing.

Information kindly provided by Dennis Kenyon.