To meet the needs of the rapidly expanding navy, Sweden looked to foreign designs and procured four ships from Italy, two each of the Psilander and Romulus classes.

[1] Italy also provided the blueprints for a more modern version of Psilander, which was used by the designers at Götaverken in Gothenburg as the basis to develop a new light destroyer.

"[4] They were small, only 78 m (255 ft 11 in) long, shorter than the British Hunt class of escort destroyers then being produced in large numbers for the Royal Navy and its allies.

[5][3] The vessels were named after characters and objects in Norse mythology, Mode and Magne, the sons of Thor, his hammer Mjölnir and Munin, one of the ravens that serve Odin.

[4] During World War II, they served as part of the Swedish coastal fleet enforcing the country's neutrality but suffered no loss.

[11] Following the war, they escorted major warships like the anti-aircraft cruiser Gotland on goodwill visits to countries like Belgium, Ireland and France.