Born Hornsea, 1894, the son of Henry Ollerenshaw Jackson, a Merchant and Bertha Amelia Smith of Eastgate, Hornsea. He had three sisters, Phyllis Mary born in 1893, Enid Bertha in 1900 and Dorothy Francis in 1902. He went to St Bede's School in Hornsea and worked as a clerk for an Oil Merchant in Hull before he joined the war early in the campaign. Henry joined the 5th (Cyclist) Battalion East Yorkshire Regiment. The 5th Battalion remained in the UK throughout the war, but at some point Henry was transferred into the 1st/4th Battalion prior to embarking for Boulogne in France when in May 1915 it was attached to the 150th Brigade 50th (Northumbrian) Division and went into action. From then on the Division was involved in some of the heaviest and bloodiest battles of the war on the Western Front. One of the most famous locations on the 1916 battlefields of the Somme was the Butte de Warlencourt, an ancient mound dating back to Roman times. It was held by the Germans and due to its excellent observation potential it was surrounded by barbed wire and with a strong machine gun presence it was fercely defended by them. The Butte was not taken by the Allied forces during the 1916 Somme Offensive but on the 5th November the 50th Division did manage to reach it briefly. Henry was killed in action on the 26th October 1916 possibly during the attack on the Butte. He was clearly a well respected, brave and courageous soldier who was promoted through the ranks to become a 2nd Lieutenant and posthumously awarded the Military Cross. The citation for this award given for conspicuous gallantry in action appeared in the London Gazette of the14th November 1916. "During an attack he laid a wire up to the second objective over ground swept by shell and machine gun fire. He formed a signal station in a shell hole within ten yards of the second objective thereby enabling important orders to be got through". Henry's grave is identified as B.31 in The Bazentin-le-Petit Communal Cemetery Extension, Somme, France