Frank Buckles, who celebrated his 110th birthday on February 1, lied about his age in order to join the army at age 16. He became one of nearly 5 million Americans who enrolled and served in the war from 1917 to 1918.
In 1941, while working as a civilian in the Phillippines, he was captured by Japanese forces and held prisoner for 38 months during World War II before being rescued by a military raid.
With Buckles' death, only a 109-year-old Australian man and a 110-year-old British woman are believed to still be alive from the estimated 65 million people who served in the war.