After the ship commissioned on 9 April 1932, she was assigned to the
2nd Destroyer Flotilla of the Home Fleet.
Cygnet spent a lot of time in dockyard hands during her first two years of service. She was repaired at
Devonport in November 1932 – January 1933, March–May, July–August and November 1933 – January 1934 before deploying to the
West Indies with the Home Fleet between January and March 1934. The ship required more repairs upon her return in April–May and then a refit from 25 July to 31 August 1934.
Cygnet was detached from the Home Fleet during the Abyssinian Crisis, and deployed in the Red Sea from September 1935 to April 1936. The ship returned to the UK in April 1936 and refitted at Devonport between 20 April and 18 June before resuming duty with the Home Fleet. In July–August she was deployed for patrol duties off the Spanish coast in the
Bay of Biscay to intercept shipping carrying contraband goods to Spain and to protect British-flagged shipping during the first stages of the
Spanish Civil War.
Transfer to the Royal Canadian Navy Together with her sister ,
Cygnet was sold to Canada on 20 October 1936 for a total price of £400,000. She was refitted again to meet Canadian standards, and handed over on 1 February 1937. The ship was renamed as HMCS
St. Laurent and commissioned into the RCN on 17 February.
St. Laurent was assigned to
Halifax,
Nova Scotia and arrived there in May. She remained there for a year before she was transferred to
Esquimalt in 1938. On 9 June,
St. Laurent was ordered to
Le Havre, France to evacuate British troops, but none were to be found and the ship evacuated a small group of French soldiers further up the coast on 11 June. The ship was taken under fire by a German artillery battery near
Saint-Valery-en-Caux, but she was not hit and
Lieutenant Commander H.G. DeWolf, the ship's captain, ordered her to return fire although no results were noted. After returning to England,
St. Laurent escorted several troop convoys on the last legs of their journeys from Canada, Australia and New Zealand in mid-June and was assigned to escort duties with Western Approaches Command afterwards. On 2 July, whilst escorting the British
battleship ,
St. Laurent received word that the unescorted British passenger ship had been torpedoed by , about northeast of
Malin Head,
Ireland. Arriving some four and a half hours after the
ocean liner sank, the ship rescued 857 survivors, including German and Italian
prisoners of war. Together with the British
sloop , she badly damaged the whilst defending Convoy HX 60 on 4 August. On 2 December,
St. Laurent rescued survivors from the
armed merchant cruiser that had been torpedoed and sunk by as well survivors from the British
oil tanker Conch. After refitting at Halifax from 3 March to 11 July 1941,
St. Laurent was assigned to the 14th
Escort Group of the RCN's
Newfoundland Escort Force which covered convoys in the Mid-Atlantic.
St. Laurent was transferred to the Mid-Ocean Escort Force in December and remained until March 1943. She was given a lengthy refit at Halifax in April–August 1942. The ship was refitted in
Dartmouth, Nova Scotia, between 17 August and December 1943. On 10 March 1944,
St. Laurent was credited with sinking in the North Atlantic, along with the destroyer , and
frigates and . 'Y' gun was also removed to allow her depth charge stowage to be increased to at least 60 depth charges. In May 1944 she was transferred to the 11th Escort Group to support the Allied
landings in Normandy. On D-Day itself – 6 June 1944 – she was deployed with the Canadian destroyers , , and stationed in the entrance to the
English Channel to prevent U-boat attacks on the invasion convoys. Later she was deployed with her group in the
Bay of Biscay for anti-submarine operations. On 8 August she was unsuccessfully attacked by a
glide bomb, and on the 13th she and
Ottawa rescued survivors from which had been sunk with depth charges by a
Sunderland aircraft. These duties continued into October, when she returned to Canada to refit. Conducted at
Shelburne, Nova Scotia, the refit lasted from November 1944 to 20 March 1945.
St. Laurent returned to service in April 1945, and was attached to the Halifax Escort Force for convoy defence off the east coast. After the German surrender on 6 May, she was employed as a troop transport, until paid off on 10 October 1945. The ship was sold for scrap and broken up in 1947. ==Notes==