William Edward Parsons, 5th Earl of Rosse, Baron of Oxmantown, 8th Baronet of Birr Castle, was born 14 June 1873 to Laurence Parsons, 4th Earl of Rosse, and Lady Frances Cassandra Hawke. Before inheriting the earldom, Lord Oxmantown was commissioned into a militia battalion of the West Yorkshire Regiment in 1896, and was swiftly promoted to Lieutenant. A year later, he was commissioned as a regular officer in the Coldstream Guards, and later transferred to the Irish Guards on its formation in 1900, and promoted to Captain. On 19 October 1905 he married Lady Frances Lois Lister-Kaye, daughter of Sir Cecil Lister-Kaye, 4th Baronet and Lady Beatrice Adeline Pelham-Clinton. Upon the death of his father, William Parsons became the 5th Earl of Rosse and head of the Parsons family. He was promoted to Major in 1906 and resigned in 1908. In 1911 he was elected a Representative Peer. Lord Rosse returned to military service to fight in the First World War, was wounded in action, and died on 10 June 1918.