She was outfitted with a variety of guns, depth charge tracks, Y-guns, and Mousetrap and placed in service as a patrol vessel.

Muskeget was built as the commercial cargo ship SS Cornish in 1923 by Bethlehem Shipbuilding Corporation at Sparrows Point in Baltimore, Maryland.

Commissioned into the Coast Guard as USCGC Muskeget (WAG-48) on 1 July 1942,[1] she was assigned Boston, Massachusetts, as her home port[1] and to duty with the North Atlantic Weather Patrol.

[1][2] At 14:54 hours on 9 September 1942, the German Navy submarine U-755, operating as part of a wolfpack, sighted Muskeget emerging from a rain squall in a heavy swell about 400 nautical miles (740 km; 460 mi) east of Newfoundland and misidentified her as an auxiliary merchant cruiser.

U-755, commanded by Kapitänleutnant Walter Göing, fired two torpedoes, heard the sounds of Muskeget's boilers exploding and bulkheads collapsing as she sank, then surfaced and found a life raft and survivors in the water, but little wreckage.

[2] Although the other personnel lost with Muskeget all received a posthumous award of the Purple Heart, the four civilian Weather Bureau meteorologists – Luther H. Brady, Lester S. Fodor, George F. Kubach, and Edward Weber – did not.

The four men received the Purple Heart posthumously in a ceremony at the Naval Heritage Center auditorium at the United States Navy Memorial in Washington, D.C., on 19 November 2015.

[2] American Legion Post 2543 in Plattsmouth, Nebraska, is named for Fireman First Class Harold Wolever, Jr., a Coast Guardsman who died in the sinking of Muskeget.