Originally named the William J. Duane after the eleventh Secretary of Treasury, she was built in 1936 by the Philadelphia Navy Yard in Pennsylvania and commissioned on August 1 of the same year. From her commission until 1939, she patrolled the Bering Sea, off the coast of Alaska. In 1939 she was reassigned to Destroyer Division 18, Neutrality Patrol, in the North Atlantic. This division's mission was to ensure the safety of commercial vessels hailing from non-belligerent nations.
In 1941, the Duane was the first vessel to initiate the opening of an ocean station in the Atlantic Ocean, east of Bermuda. These ocean stations were primarily emergency landing sites for aircraft crossing the Atlantic, but were also used to monitor the weather and collect oceanographic data. Later in 1941, in preparation for the war, the Duane was transferred to the United States Naval Neutrality Patrol (later named the United States Atlantic Fleet). The Duane, along with many other Cutters, established her role in the World War II as an anti-submarine vessel.
On June 14, 1941 the German U-boat, U-77, torpedoed the British vessel Tresillian. The Duane rushed to aid the British merchant ship and rescued 46 survivors. In August, she was reassigned to Greenland's west coast to search for possible German airfield sites that might threaten North America. She was then transferred to the North Atlantic and equipped with specialized armament to track and destroy submarines.
In February, 1942, the Duane rescued 250 survivors of a 600-man crew from the U.S. Army transport Dorchester. In April 1943 she became a member of the eight-vessel Task Unit 24.1.3. This Task Unit was assigned to protect 54 merchant ships headed for Firth of Clyde, Scotland. On April 17, the merchant ship Fort Rampart was attacked by torpedoes presumably from the submarine U-175. The Duane aided in the sinking of the U-175 and picked up 22 German survivors.
In 1944, the Duane became the first Coast Guard Cutter to be declared an Amphibious Task Group Flagship. This new flagship was part of the Operation Dragoon which aided in the August 9 invasion of Southern France. This invasion was the turning point which led to the end of the World War II.
After the war, the Duane was reconstructed and returned to peacetime service as an ocean station vessel. On May 4, 1957, the Finnish freighter Bornholm suffered a cracked hull after a storm. The Duane came to the Bornholm rescue, saving the entire 28-man crew. Later that year, she was transferred to Southern Vietnam, Coast Guard Squadron 3 Operation Market Time, as a patrol vessel. Back at war between 1957 and 1968, she successfully patrolled the southern coast of Vietnam and destroyed 29 enemy formations. In 1968, she again resumed duties as an ocean station vessel. After the closure of the ocean stations in 1975, the Duane began a five-year routine patrol which included drug enforcement. In 1978, during one of her many drug raids, the Duane seized the Southern Belle for possession of marijuana.
In 1980, the Duane, along with other Cutters, was an escort vessel during the Mariel Boat Lift. During this boat lift she escorted thousands of Cuban refugees into the United States. On August 1, 1985 after 49 years of service, the Duane was decommissioned.
Following her decommission, the Duane was donated to the Keys Association of Dive Operators (KADO) by the U.S. Coast Guard to aid in the rebuilding of the Florida Keys coral reefs.