Major Longmore was the son of the 1st Hertfordshire Regiment’s first Commanding Officer Sir Charles Longmore. He went to France with the 1st Herts in November 1914. After the War, he returned to work at the family law firm in Castle Street, Hertford, rising to the position of Clerk to Hertfordshire County Council and Clerk of the Peace.
The dress uniform dates to around the period of the Regiments foundation in 1908 and bears Lieutenant shoulder insignia. By 1914, Philip had risen to the rank of Captain, and was a Major by the end of the war. His war medals and helmet are also pictured.