The last veteran of World War I was a waitress, and for 90 years no one knew her name.

Florence Green, a member of Britain’s Royal Air Force who was afraid of flying, died in England on Saturday, two weeks shy of her 111th birthday. She was believed to have been the war’s last living veteran — the last anywhere of the tens of millions who served.

Mrs. Green, who joined the R.A.F. as a teenager shortly before war’s end, worked in an officer’s mess on the home front. Her service was officially recognized only in 2010, after a researcher unearthed her records in Britain’s National Archives.

That Mrs. Green went unrecognized for so long owes partly to the fact that she served under her maiden name, Florence Patterson, and partly to the fact that she conducted herself, by all accounts, with proper British restraint, rarely if ever flaunting her service.

It also owes to the fact that her life followed the prescribed trajectory for women of her era: by the time the 20th century had run its course, Mrs. Green had long since disappeared into marriage, motherhood and contented anonymity.