She was born Russian. Built in 1916 at the Kolomna yard near Moscow, the minelayer Voin went to the Imperial Navy's Baltic force and took part in a handful of wartime operations before the empire that ordered her came apart. When Russian forces pulled out of Finland during the civil war, they left her behind. The new Finnish Navy christened her M1 — Miinalaiva 1, minelayer number one — and found itself with the largest ship in its fleet, 776 tons on a hull fifty metres long. From the summer of 1919 she patrolled off Koivisto, screening a British naval detachment that operated against Russian vessels there until the Treaty of Tartu in 1920. In 1936 the navy gave its major units proper names, and M1 became Louhi, after the shape-shifting sorceress-queen of the Kalevala who rules the cold north and sends the frost.

By any technical measure Louhi was a poor minelayer. She was slow, she handled badly in a seaway, and her holds were too small for the loads she was meant to carry — so poor a fit that in peacetime the navy converted the storage space into crew quarters and used her as a depot ship. Then the Winter War began, and it turned out she was the only vessel Finland had that could lay a large minefield at all. The rest of the capability amounted to five small T-class mine boats, some submarines, and requisitioned civilian craft. Of roughly 1,900 mines the Finnish Navy laid during that war, Louhi put down about a third. She worked the seaways off Kökar and Utö on the very first night. On 3 December, mid-operation near Nyhamn, two of her own mines detonated and she had to break off and go back later to finish.

Her most consequential work was the barrier across the narrows near Märket, the low divided skerry in the Sea of Åland where the Finnish and Swedish borders meet, guarding the way north into the Gulf of Bothnia. Louhi laid mines there on 9 and 14 December 1939, and when Soviet submarines were observed slipping through anyway, she returned on 10 January to thicken it, followed two days later by the auxiliary minelayer Baltic; the auxiliary Frej strung kilometres of anti-submarine netting behind them. It worked well enough to keep Soviet boats largely out of the Gulf of Bothnia. Finland's minelaying capacity was small, but the returns were disproportionate: at least two Soviet patrol boats, a submarine, and a German cargo ship are known to have been destroyed by Finnish mines, and at least one Soviet vessel by mines from Louhi specifically. The campaign stopped in January 1940 only because the gulf froze.

By the Continuation War the Finns had two modern purpose-built minelayers, deep stocks, German influence mines of the newest pattern, and a domestic mine industry. Working with the Kriegsmarine, they closed the Gulf of Finland with a density Louhi's generation could not have managed — the mines and submarine nets between Porkkala and Naissaar penned the Soviet fleet into the eastern gulf from late summer 1943 onward. Louhi spent those years as a mother ship for submarines and an escort for merchant convoys. Then Finland signed its armistice with Moscow in September 1944 and was obliged to drive German forces off Finnish soil. The Lapland War put the old ship back to work laying mines — this time against the navy she had been cooperating with a few months earlier, and under the escort of two Soviet MO-boats. It was those Soviet crews who pulled Louhi's survivors out of the freezing water on 12 January.

For fifty years everyone assumed a mine had killed her — perhaps a Finnish one from 1941, perhaps a German one from 1944. Divers who reached the wreck found damage to the hull outside the engine room that did not fit a mine. Archival research in Germany in the 2000s produced a likelier answer: U-370, patrolling the same water, had fired two acoustic homing G7es torpedoes at passing ships, and one of them appears to have run onto the Finnish minelayer. The sinking position had been marked on charts for decades, and when divers finally went looking, there was nothing there. The Badewanne team located the wreck elsewhere in May 2015, roughly 7.5 nautical miles southeast of the Russarö lighthouse. U-370 survived the encounter and the war, and was scuttled by her own crew in Geltinger Bucht on 5 May 1945.