A World War Two veteran said he spent three hours opening cards following a friend's plea on Facebook to stop him feeling lonely this Christmas.
"Another big pile has just turned up, my front room is full," said Ted Owens, 93, a former Royal Marines Commando from Pembroke Dock, Pembrokeshire.
Author Mark Llewhellin, a former Army Commando, met Mr Owens a year ago when he interviewed him.
He got dozens of cards after posting a request on Facebook on Wednesday.
Mr Llewhellin, from Haverfordwest, said he had taken Mr Owens to visit barracks around the country.
He said: "He lives on his own and he does sit in and look at four walls a lot. It's quite lonely really. It's great to take him out to these places but, after that big thrill, he's on his own.
"He's got an incredible story, but the most incredible thing is he's just so nice and humble and down to earth.
"This Christmas, I thought to myself 'can anyone send him some cards or gifts?' He's been bombarded and he's even had a phone call from another Commando in Australia."
Mr Owens said he joined the Royal Marines aged 18 and receiving all his cards and gifts had "made me feel young again".
"I was on the D-Day landings and was very badly wounded on the first day. I was two-and-a-half months in hospital then I went back to my unit and went all through France and Belgium," he said.
"Then I was on the Walcheren landings, a big island off the Dutch coast, and got wounded by a mine. I was also in the Battle of the Bulge.
"I'm a very lucky man, I'm fit as a fiddle."