Evelyn Francis Edward Seymour, 17th Duke of Somerset DSO OBE KStJ DL (1 May 1882 – 26 April 1954) was a British Army officer, landowner, peer, and for eight years Lord Lieutenant of Wiltshire. He was also a baronet.
The son of Edward Seymour, 16th Duke of Somerset, by his marriage to Rowena Wall, Seymour was born in Colombo, Ceylon. He returned to England and was educated at Blundell's School, Tiverton, and later at the Royal Military College, Sandhurst. He was gazetted a second lieutenant on the Unattached List in January 1901, before being attached to the Royal Dublin Fusiliers.
Seymour served throughout the South African War and received the Queen's South Africa Medal with five clasps. He took part in the operations in the Aden Protectorate in 1903.
In April 1913, Seymour, then of the Royal Dublin Fusiliers, was appointed adjutant of the 25th (County of London) Cyclist Battalion of the London Regiment, in which posting he continued until 1916, before returning to the Royal Dublin Fusiliers to take command of its 10th Battalion. In December 1917, he was promoted Acting Lieutenant Colonel. In 1918, he was awarded the DSO and in 1919 he served in the Adjutant General's department of the War Office. He was appointed OBE in 1919 and retired from the service in 1920. He succeeded to his father's dukedom in 1931.