Just before parachuting into Nazi-occupied Europe, Fayette Richardson asked himself an existential question: "My God, Most Powerful, what am I doing here?"

The thought had to be on the minds of myriad soldiers on June 6, 1944. It was D-Day, the launch of a long-awaited campaign by the U.S. and British armies to free the nations of Western Europe that Hitler had conquered.

Mounted from airfields and ports in Great Britain, it was the largest amphibious assault in history. More than 155,000 Allied troops landed at Normandy, France, that day.

Code-named Operation Overlord, it dramatically changed the course of World War II. Seventy-five years later, the ranks have thinned of those who braved machine gun fire on French beaches that were marked on their maps with American names like Utah and Omaha.

Richardson died in 2010. But fortunately for us and for future generations, he and other veterans kept diaries, wrote memoirs or recorded their recollections. Oral history was in its infancy when Stephen Ambrose began tape recording D-Day veterans, observed Toni Kiser, assistant director for collections management at The National WWII Museum in New Orleans.

"Ambrose, who began collecting the oral histories housed in our archives, was a distinguished historian," Kiser said.