The world's oldest man, 113-year-old World War One veteran Henry Allingham, died yesterday after spending his final years reminding Britain about the nine million soldiers killed during the conflict.

Allingham was the last surviving original member of the Royal Air Force, which was formed in 1918. He made it a crusade to talk about a conflict that wiped out much of a generation. Though nearly blind, he would take the outstretched hands of visitors in both of his, gaze into the eyes of children, veterans and journalists and deliver a message he wanted them all to remember. "I want everyone to know," he said. "They died for us." Only a handful of World War One veterans remain of the estimated 68 million mobilised. There are no French veterans left alive; the last living American-born veteran is Frank Woodruff Buckles of Charles Town, West Virginia.

"It's the end of a era – a very special and unique generation," said Allingham's longtime friend, Dennis Goodwin, who confirmed Allingham's death. "The British people owe them a great deal of gratitude."

Born 6 June 1896, Allingham left school at 15 and was working in a car factory in east London when war broke out in 1914.

He spent the war's first months refitting trucks for military use, but when his mother died in June 1915, he decided to join up after seeing a plane circling a reservoir in Essex, east of London.

"It was a captivating sight," he wrote in his memoir. "Fascinated, I sat down on the grass verge to watch the aircraft. I decided that was for me."

Only a dozen years after the Wright brothers first put up their plane, Allingham and other airmen set out from eastern England on motorised kites made with wood, linen and wire. They piled on clothes and smeared their faces in Vaseline, whale oil or engine grease to block the cold.

"To be honest, all the planes were so flimsy and unpredictable – as well as incapable of carrying large fuel loads – at the start of the war that both British and German pilots would immediately turn back rather than face each other in the skies if they did not enjoy height supremacy," Allingham would later write. "But I remember getting back on the ground and just itching to take off again."

He fought in the Battle of Jutland, the largest naval battle of World War One. He served on the Western Front, by now armed with a machine gun. He was wounded in the arm by shrapnel during an attack on an aircraft depot, but survived.

After the war he worked at the Ford motor factory and raised two children with his wife, Dorothy. She died in 1970, and when his daughter Jean died in 2001, friends say he waited to die, too.