She served with the Royal Canadian Navy during the Second World War and saw action primarily as a convoy escort in the Battle of the Atlantic.

She was returned to United Kingdom following the war and quickly sold to Denmark, who renamed the vessel Niels Ebbesen.

Annan was ordered by the Royal Navy on 26 December 1942 and laid down on 10 June 1943 by Hall, Russell & Co. Ltd. at their shipyard in Aberdeen, Scotland.

[2] The vessel was launched on 29 December 1943[2] and was handed over to the Royal Canadian Navy for commissioning as HMCS Annan on 13 January 1944 at Aberdeen.

[3] However the following month, Annan returned to the United Kingdom and was handed back to the Royal Navy at Sheerness on 20 June 1945.