Veterans Day was originally called Armistice Day to honor the pact signed to end World War I on November 11, 1918. But with only three servicemen still alive, this is potentially the last year the holiday will have a living connection to the vets that inspired it. Meet the last of their kind:

Claude Choules, 108 (Great Britain)

The only one of the three who saw active combat duty, Choules now lives in a retirement community in Perth, Australia. After enlisting in the British navy in 1916 (at age 15), he "witnessed the surrender of the German Fleet near Firth of Forth, Scotland, in 1918." Choules later served as a torpedo officer in World War II. He has just published his first book, an autobiography called Last of the Last. (Watch an ITN news segment about Claude Choules)

Frank Buckles, 108 (U.S.)

This Missouri native drove an ambulance on the Western Front in 1918. He is the last of nearly five million U.S. "doughboys" (as WWI infantrymen were known). In a recent interview, he attributed his longevity to exercise and "a desire to live." Last week, Congress honored him by passing the Frank Buckles World War I Memorial Act. Upon his death, he’ll be buried in Arlington National Cemetery. (Watch an ABC News segment on Frank Buckles)

John Babcock, 109 (Canada)

After joining the Canadian Expeditionary Forces as a teenager, Babcock went to Europe to fight, but the war ended before he ever reached the front lines. He has called this a "disappointment" because he never felt like "a real soldier." Asked how he would feel about one of his grandchildren serving in Iraq, he has said he "wouldn’t like it." Babcock moved to the US shortly after WWI and today lives in Spokane, Washington. Upon his 107th birthday he received congratulations from Queen Elizabeth II. (Watch an interview with John Babcock)