Originally completed as a USS Bouge class carrier, modified by having petrol stowage reduced to 50,000 gallons (ballasted in compensation with about 1,000 tons) and US 4 inch guns instead of the original US 5 inch. In 1943 this vessel was obtained through the United States lend lease programme.

In May 1943 HMS Fencer was tasked to supply air escort for the North Atlantic convoys. In September she was a member of the 8th Search Support Group deployed in escorting a special convoy that was transporting the personnel and installations for number 247 Royal Air Force group on the Azores Islands of Fayal and Terceira. By October she was again in the North Atlantic on convoy duties.

During January – February 1944 Fencer was a member of the 10th Anti Submarine Search Group and was serving on North Atlantic convoy duties. During March – April while on Arctic convoy duties, her aircraft and those of the aircraft carriers HMS Victorious, HMS Furious and the escort carriers HMS Emperor, HMS Pursuer and HMS Searcher were involved on a raid carried out on the German battleship Tirpitz known as operation “Tungsten”, putting the battleship out of action for three months. In May while on Arctic convoy duties, she proceeded to the northern Norwegian coast to carry out another raid on the Tirpitz. Due to adverse weather, flying conditions became impossible, and the task force retreated. During this time her aircraft were involved in sinking three German submarines U-277, U-959 and U-674. In October 1944 HMS Fencer accompanied by the escort carrier HMS Trumpeter, four British and two Canadian destroyers carried out an air mining operation and an air strike on German shipping routes off Norway near Frohavet.

In 1945 Fencer was transferred to the British Pacific Fleet. July 9-11th saw the aircraft carrier docked at the Selborne dry dock at Simonstown, South Africa where she was temporary converted for trooping duties.

On 11 December 1946 Fencer was returned to the US Navy, and was subsequently converted for merchant service and renamed Sydney. In 1968 Sydney was renamed Roma, and later that year resold to become the Galaxy Queen. Sometime after this date she changed owners twice, becoming Lady Dina in 1972 and then Cariba II in 1973. In September 1975 she was sold to be broken up for scrap at La Spezia, Italy.

Her wartime badge can be seen displayed on the side of the Selborne dry dock wall.

Commanding Officers:
Capt. Edmund Walter Anstice, RN
August 1942 – 19 January 1944

A/Capt. Wolf Walter Rudolf Bentinck, RN
19 January 1944 – 18 June 1944 A/Lt.Cdr. John Assheton Eardley-Wilmot, DSC, RN
18 June 1944 – 15 August 1945

A/Cdr. Rodney Charles Vesey Thomson, DSC, RN (retired)
15 August 1945 - still in command in October 1945 according to the Navy List