After the attack on Pearl Harbor the captain, Knud L. Hansen, offered the ship to the U.S. government as a training vessel. This offer was accepted, and "Danmark" moved to New London, Connecticut to train cadets at the United States Coast Guard Academy there. Approximately five thousand cadets were trained before the ship was returned to Denmark in 1945. Her designation in the U.S. Coast Guard was USCGC "Danmark" (WIX-283). She resumed her training duties the following year. In recognition of her wartime service, a bronze plaque was placed on the mainmast, and "Danmark" was given the honor of leading the parade of ships at the 1964 Worlds Fair in New York. Experience with "Danmark" led to the acquisition of the USCGC "Eagle" from Germany at the end of the war as a training vessel.