Archer was born on 6th November 1890 in Bromsgrove, the son of the 1st Earl of Plymouth and the Countess of Plymouth. In 1911 he was living at St Fagan’s Castle, St Fagans, Glamorganshire with his mother Alberta Nichoria Plymouth. From De Ruvigny’s Roll of Honour – 3rd son of Robert, Earl of Plymouth and his wife Alberta. Served in the 3rd Battalion, the Coldstream Guards (joined 8th September 1911) and served with the Expeditionary Force in France & Flanders. His rank was Lieutenant. Archer was killed in action on 25th August 1914 aged 23 and is buried at B. 1., Landrecies Communal Cemetery. He was educated at Eton and Trinity College, Cambridge.