Washington (CNN) -- President Barack Obama and Vice President Joe Biden made a surprise visit to Arlington National Cemetery on Tuesday to honor Frank Buckles, the last American veteran of World War I to die.
Obama and Biden met with Buckles' family shortly before his funeral service.
Buckles passed away on February 27, less than a month after his 110th birthday. During what was then known as the "Great War," he served as a U.S. Army ambulance driver in Europe, rising to the rank of corporal before the conflict ended.
Buckles also served in World War II, having taken up a career as a ship's officer on merchant vessels. He was captured by the Japanese in the Philippines during World War II and held prisoner of war for more than three years before he was freed by U.S. troops.
Late in his life, he became a public advocate for a national World War I memorial in Washington comparable to those for veterans of World War II, Korea and Vietnam.
While Buckles received a special burial at Arlington, he did not lie in honor in the U.S. Capitol Rotunda -- a tribute his family and several of members of Congress sought as a final, formal tribute to all the veterans of World War I.
More than 116,000 Americans were killed and over 204,000 were wounded in the 19 months of U.S. involvement in World War I, according to the Congressional Research Service. The overall death toll of the 1914-18 conflict was more than 16.5 million, including nearly 7 million civilians, and more than 20 million wounded.
Following the death of Buckles, there are only two known living veterans of World War I, both of whom are British.
CNN's Alan Silverleib and Richard Greene contributed to this report