As the U.S. Coast Guard turns 231 years old this week, we take a look at the hardware the unsung seagoing coasties used in World War II. 

Founded as Alexander Hamilton’s Revenue-Marine on Aug. 4, 1790, besides its seagoing law enforcement mission – which included fighting pirates – the Coast Guard or its preceding components have been active in every single American war to include the War of 1812, the Mexican-American War, the Civil WarSpanish-American War, both World Wars, the Korean WarVietnam, and the Gulf Wars

Speaking of WWII, on November 1, 1941, President Franking D. Roosevelt signed an executive order reassigning the service’s duties from the Treasury Department to the Navy a full five weeks prior to the Japanese attack on Pearl Harbor. 

In all, 214,000 personnel served in the Coast Guard during WWII in a wide mix of missions. 

The most high-profile fighting units in the service were its cutters and patrol boats, which sailed off to escort convoys against U-boats and slug it out on the beachline in amphibious assaults from North Africa and Guadalcanal to Normandy and Okinawa. 

The largest guns on the Coast Guard's newest cutters were low-angle 5-inch mounts, which were slow to track and load, but could crack the hull of a surfaced enemy submarine. One such cutter, Campbell (WPG-32), sank submarine U-606 in a close-in action that ended with the cutter landing hits on the surfaced German U-boat with her deck guns. 
Original caption: "Coast Guard Cutter's Gun Blasts at U-boat. Somewhere in mid-Atlantic, the three-inch gun of a U.S. Coast Guard cutter fires point-blank at an enemy sub, as the cutter protects a convoy."


Original caption: "A Coast Guard gun crew stands at its battle station, manning an anti-aircraft battery pointed skyward against raids by Japanese bombers." The crew is manning a 40mm Bofors anti-air artillery piece. 
Original caption: "U.S. Coast Guardsmen fight off attacking Japanese planes during the invasion of Cape Gloucester, New Britain. Behind the gun a Coast Guardsman can be seen pointing at a plane overhead." The gun is a 20mm Oerlikon. 
Original caption: "Aboard a Coast Guard combat cutter proceeding through European waters, two Coast Guardsmen snatch a few minutes sleep as a shipmate keeps alert watch for signs of enemy attack. The sleeping men are off watch, but they stay close by their guns, ready to spring into action."


Original caption: "Aboard a Coast Guard fighting ship in the North Atlantic, this champion 20mm crew on battle maneuvers aim their gun low to knock off torpedo bombers skimming the surface of the sea."

In addition to the 1,677 Coast Guard-flagged craft in active service at the end of the war, 56,000 Coast Guardsmen manned 326 Navy ships – including 76 landing ships, 21 cargo and attack-cargo ships, 75 frigates, and 31 transports – as well as 254 Army vessels. 

Official caption: "A gun crew aboard a Coast Guard-manned frigate in the southwest Pacific. On call to general quarters, these Coast Guardsmen man a 20mm AA gun." 


Original caption: "Aboard a troop transport somewhere in the southwest Pacific, a Coast Guard gun pointer rests on the barrel of his gun after having smacked a Japanese torpedo plane out of the skies. Flag on the gun's barrel indicates the successful action." 

To patrol 3,700 miles of American beaches for saboteurs landing from the sea, a scratch force of 24,000 officers and men, assisted by over 2,000 sentry dogs and nearly 3,000 horses, was built from the ground up almost overnight. These men carried M1903 Springfields, M1911 .45 ACP sidearms, and a mix of shotguns and submachine guns, with the Reising being one of the more popular. 

Original caption: "Two Coast sentries silently making their rounds in the lonely night." Note the M1903 Springfield .30-06 rifle


M1911s were also very common on beach and harbor patrol against enemy saboteurs. 
The Reising subgun, not well-liked in overseas use, was pressed into service with the Coast Guard during WWII.
The small arms lockers on cutters were much the same collection of sub guns and M1903s. In one incident with the cutter Icarus and a German U-boat off the coast of North Carolina, the endgame came down to small arms. 

At its peak strength on September 1, 1945, the Coast Guard totaled 170,480, including 9,624 uniformed women serving in the SPARS.

1943 – U.S. Coast Guard SPAR packing an M1903 Springfield rifle at the Cleveland Armory. 

Some 125,000 personnel served in the Coast Guard's Temporary Reserve during the conflict, the latter manning the myriad “Corsair Fleet” of 2,998 converted motor and sail craft used for local patrol that had been acquired through purchase, charter, or gift, principally to combat the submarine menace along the coasts. These ships, dubbed the Hooligan Navy, were armed with small arms and obsolete guns, such as slow-to-load 37mm and 57mm deck guns leftover from chasing bootleggers during Prohibition. 

Prior to WWII, the Coast Guard widely used small deck guns, termed 1-pounders and 3-pounders due to the weight of their shells, for use in sending a "shot across the bow" of a smuggler. These guns were pressed into use during the war to help arm small craft on the coastal picket patrol. 
And, naturally, SMGs like the Thompson were used on these converted pleasure craft and trawlers as well. 

Some 28 USCG-manned vessels were lost during WWII, adding 572 Coast Guardsmen to the massive butcher’s bill of the conflict.

For more on the USCG in WWII, check out the Coast Guard Historian’s portal. All photos via the National Archives' USCG 1939-67 collection.

revolver barrel loading graphic