Klein was awarded the Bronze Star and the Purple Heart, and the prestigious Legion of Honour by France.
This year, the D-Day Overlord association raised €4000 ($6464) in crowdfunding to bring him over from his home in Glenview, Illinois, where he said: "I'm not a hero. The real heroes are those who have lost life here."
Describing him as "one of the great celebrities" of this year's anniversary, the association said he had signed "hundreds of autographs" and attended numerous commemorations, "marking all those he met by his incredible kindness".
However, weeks after his return to the US, Captain Klein dropped a bombshell by confessing to his family and supporters that he was nowhere near the beaches of Normandy. In fact, he was in Northern Ireland with the B Battery of his artillery regiment (46th Field Artillery Battalion, 5th Infantry Division).
The veteran owned up after being outed, according to D-Day Overlord, by "several" historians, including Marty Morgan and Gary Sterne, who is the owner of Maisy's battery museum, and who could find no trace of his presence.
On August 18, their allegations were confirmed by "American veterans in the same unit as George Klein" who "confirmed he was with them and hadn't taken part in the fighting at the Pointe du Hoc".
"George Klein arrived in Normandy in July 1944," Marc Laurenceau, head of the Overlord D-Day association, told local paper La Renaissance Le Bessin.
"I'm in contact with his family with whom I have become friends. They are devastated," he said. "So are we, as we believed his story. We put in a lot of effort to get him to Normandy."
Laurenceau said that Klein had got away with the subterfuge due to "impeccable attention to detail" about the three days spent fighting the Germans.
Besides, his story had every reason to be plausible as he had truly been a Ranger and but had "broken his ankle during a climbing training during the year 1943 and had to give up any hope of remaining in this elite unit".
He managed to explain his absence from the list of the 225 Rangers who really took part in the assault by claiming to be a "supernumeray" lieutenant drafted in at the last minute to replace a platoon leader.
Despite his fake account, Overlord D-Day association said Klein should "not be ashamed of his real contribution to the liberation of Europe", as he was seriously wounded in combat in the Moselle region on November 17, 1944.
"But the prestige of a unit like the Rangers, as well as certainly the disappointment of not having participated in a major battle of World War II [even though he had risked his life on numerous occasions], have probably strengthened the temptation," it said.
"Trapped into a lie of that shaped him in the eyes of his entourage and from which he could no longer escape, he finally resolved to tell the truth."
The association said the "sad story" was unfortunately not an isolated case, citing Howard Manoian and Eugene A. Cook Jr, unmasked in 2009 and February 2017. They both fabricated a career in American airborne troops, also participating in numerous commemorative ceremonies bearing the insignia of units to which they had not belonged.
