William Edward Parsons, 5th Earl of Rosse (14 June 1873–10 June 1918) was the son of Lawrence Parsons, 4th Earl of Rosse and Frances Cassandra Hawke. He was elected a Representative Peer in 1911. He fought in the First World War and died on 10 June 1918 at age 44, from wounds received in action.
Lord Oxmantown, as he then was, was commissioned into a militia battalion of the West Yorkshire Regiment in 1896 and promoted Lieutenant shortly afterwards. He was commissioned as a regular officer in the Coldstream Guards in 1897, but transferred to the Irish Guards on its formation in 1900. He was promoted Captain in 1900 and Major in 1906. He resigned his commission in 1908, but returned to service in the First World War.
He married Frances Lois Lister-Kaye, daughter of Sir Cecil Lister-Kaye, 4th Baronet and Lady Beatrice Adeline Pelham-Clinton, on 19 October 1905. They had three children:
| Honorary titles | ||
|---|---|---|
| Preceded by The Earl of Rosse |
Lord Lieutenant of King's County 1909–1918 |
Succeeded by Edward John Beaumont-Nesbitt |
| Peerage of Ireland | ||
| Preceded by Lawrence Parsons |
Earl of Rosse 1908–1918 |
Succeeded by Lawrence Parsons |