Coast Guard Under the United States Navy

The United States Coast Guard and the U.S. Navy have had a close relationship since the Coast Guard was established in 1915. As a result, Coast Guard personnel within Navy ships or Coast Guard units may be documented in Navy records. 

The U.S. Coast Guard was established within the Department of the Treasury on January 28, 1915. Under 14 U.S. Code § 101, this service comes under the U.S. Navy during times of war or when the President or Congress directs during periods of peace. From World War I to the present, Coastguardsmen have supported the Navy in their operations during times of war and armed conflict.

World War I

After World War I, the Office of the Secretary of the Navy discussed whether the Coast Guard should go back to its peacetime administration under the Department of the Treasury. Assistant Secretary of the Navy Franklin D. Roosevelt led this discussion, which is documented in the General Correspondence of the Secretary of the Navy and related indexes in Record Group 80: Records of the Department of the Navy.

World War II

The Coast Guard ultimately remained a separate branch during peacetime but continued its close relationship with the Navy during wartime. As a result of this relationship, some Coast Guard records from World War II are among the records of the U.S. Navy. 

Examples:

• Record Group 24: Records of the Bureau of Naval Personnel
  • U.S. Navy Deck Logs, 1941–1950 (Entry P 118-A1 and P118-A2). Typically Coast Guard crews would substitute naval crews aboard select naval ships including Destroyer Escorts, Landing Ship Tanks (LSTs), and Landing Craft Infantry (LCIs).
• Record Group 38: Records of the Chief of Naval Operations
  • Select U.S. Navy World War II War Diaries and Other Operational Reports
  • U.S. Navy World War II War Diaries
  • U.S. Navy World War II Action and Other Operational Reports
  • World War II Command Files
  • Records of the Tenth Fleet, Anti-Submarine Warfare Incident Reports

These series are arranged by command hierarchy, with a section of record materials from the Coast Guard following the main section of reports from naval commands.

Korean War

During the Korean War, the U.S. Coast Guard was specifically tasked to continue its peacetime missions by helping South Korea develop their navy, maintain port security, provide search and rescue services, provide weather and ocean reports, and operate the Long Range Aid to Navigation (LORAN) stations. In 1947, the Chief of Naval Operations determined that the Coast Guard should not be brought under the U.S. Navy in future conflicts. 

Vietnam War

During the Vietnam War, the Coast Guard established two squadrons that were deployed to Vietnam to assist in Task Force 115, Operation Market Time, the Coastal Surveillance of South Vietnam. Coast Guard Squadron One (RONONE), consisting of 26 Point-class 82-foot patrol boats, was established in 1965. In 1967, the demand for more surveillance along Vietnamese waterways led the Coast Guard to establish Squadron Three (RONTHREE). RONTHREE consisted of five High-Endurance (WHEC) cutters brought to South Vietnam to assist with searching and intercepting illegal arms and contraband along rivers and with gunfire support duty.  

In addition to the cutters, the Coast Guard provided port security, waterways detail, and explosives loading detachments (ELDs). It also set up LORAN stations to provide more accurate navigation support to ocean-going vessels sailing in that area. 

Many Coast Guard materials from the Vietnam War are still in the custody of the Naval History and Heritage Command. The Monthly Historical Summaries in Record Group 38: Records of the Chief of Naval Operations (Entry UD-UP 11-A) are among the few record series held by the National Archives that reference Coast Guard activity during this period.