In 1915 George secured a commission as 2nd Lieutenant in the Rifle Brigade and joined the 2nd Battalion in France. By 1917 the British cavalry had secured the town of Peronne. On 4 March the 2nd Rifles were kept in reserve as the 8th Division successfully occupied the German first and second lines, three miles to the north. Four days later George and his comrades were in a working party responsible for deepening a captured German trench at Bouchavesnes. It was at this point that he performed the act of valour for which he was awarded a Victoria Cross. "For most conspicuous gallantry and self sacrifice. When engaged with some other men in deepening a captured trench, their officer struck with his spade a buried bomb, which immediately stared to burn; 2nd Lieut Cates, in order to save the lives of his comrades, placed his foot on the bomb which immediately exploded. He showed most conspicuous gallantry and devotion to duty in performing the act which cost his life but saved the lives of others. This heroic young officer died of his wounds the same night, 9th March 1917.