She was originally built as a Fishery Protection Vessel for the British Royal Navy, entering service as HMS Anglesey in 1979.

After evaluation of the Scottish Fisheries Protection Agency's fishery protection vessel Jura, built by the shipbuilders Hall, Russell & Company to a trawler-like design, the Royal Navy ordered five ships of the Island-class, based on Jura's design in February 1975, with a further two ships, Anglesey and Alderney on 21 October 1977.

[3] Two Ruston 12 RK 3 CM diesel engines rated at a total of 4,380 brake horsepower (3,270 kW) drove a single propeller shaft, giving a speed of 16 knots (30 km/h; 18 mph),[2] adequate to deal with the majority of trawlers in service in European waters.

[2] The earlier ships of the class had suffered from excessive motions in high seas,[4] and so Anglesey was fitted with fin stabiliser during build.

[2] HMS Anglesey was laid down at Hall Russell's Aberdeen shipyard on 6 February 1978[5][verification needed] and launched on 18 October 1978.