Fireman Angus Nelson MacLean and 1st Lt. James Frost died on Sept. 26, 1918, off Wales, when the Coast Guard cutter Tampa was attacked by a German submarine.
The Tampa took a direct hit amidships from a torpedo and sank within three minutes, resulting in the biggest loss of life in a single day for the Coast Guard during World War I -- 111 members. Four U.S. Navy sailors also died, as well as 11 members of the Royal Navy and five civilians.
During World War I, the Purple Heart, which was created as the Badge for Military Merit by Gen. George Washington in 1782 and is given to service members who sustain injuries or are killed as a result of enemy action, was not being awarded. Even though the medal was revived in 1932, it wasn't authorized for Coast Guardsmen until 1942 and, at the time, only for those who served in World War II.
The Purple Heart was made retroactive to WWI in 1952 but, according to the Coast Guard, the Tampa crew was overlooked. In 1999, then-retired Master Chief Petty Officer James Bunch proposed that the medal be awarded posthumously to the crew.
The idea was approved by then-Commandant Adm. James Loy, and the service has been trying to track down family members ever since.
"More than 100 years after the sinking of the Tampa, the Coast Guard continues to identify families who have yet to receive their ancestor's Purple Heart Medal," service officials said in a press release.
Since 1999, at least 36 Purple Hearts have been awarded to Tampa crewmembers, with an additional 30 in the pipeline. The Coast Guard's archivist maintains a list of the ship's crew, including the four Navy personnel aboard, who have received or are eligible for the award.
Information on how families can apply is available on the Coast Guard's website.
According to the service, the Tampa was one of six cutters assigned escort duty in the North Atlantic during World War I. During its service, it lost only two ships and earned a commendation for exemplary service.
At the time of its sinking, the Tampa had just completed its 19th convoy and was traveling through the Bristol Channel, headed for Milford Haven, Wales, for coal.
The boat that sank the Tampa, UB-91, was credited with sinking three other vessels during the war. The submarine was transferred to the Royal Navy and scrapped in Briton Ferry, Wales, in 1921.
Capt. Michael Kahle, commander of Coast Guard Sector St. Petersburg, will present the medals to the families of MacLean and Frost in a ceremony at the Tampa Bay History Center.
Editor's note: This story has been updated to clarify that the Tampa sinking resulted in the largest one-day loss of life for the service during World War I. The largest single loss of life for the service occurred Jan. 25, 1945, with an explosion aboard the USS Serpens that killed 193 Coast Guard members.
-- Patricia Kime can be reached at Patricia.Kime@Military.com. Follow her on Twitter @patriciakime