In a 2011 interview, the author explained how Lee revolutionised the genre. “Up till then the dominant comic book had been the DC comics which, at that time, were always very circular. Superman or Batman would have an adventure, and at the end of the adventure they would wind up exactly where they were.” In contrast, “the Marvel characters were constantly changing”.

“As opposed to DC [Comics], where everybody got along and it was all very nice and all the heroes liked each other, … Stan Lee introduced a whole concept of characterisation to comic books and conflict; maybe even a touch of grey in some of the characters.”

Martin’s fantasy novels, adapted for the HBO series Game of Thrones, feature morally complex characters in stories that avoid a black-and-white struggle between good and evil. In his interview with the BBC in Edinburgh, the author describes encountering the Marvel character Wonder Man, who is planted among The Avengers to sabotage them. “But when the moment comes when he’s supposed to betray them and destroy them, he’s come to like them so much by being a spy among them that he can’t bring himself to do it. He sacrifices himself, and dies at the end of the issue.”

Several of Martin’s letters praising Stan Lee storylines were published in Marvel issues. One written in 1964 has resurfaced online. In another letter, printed in a 1961 issue of Fantastic Four when Martin was 13, he asked: “In what other comic mag could you see things like a hero falling down a manhole, a heroine mistaking a toy inventor for a criminal, and the President of the USA leaving a conference that may determine the fate of the world to put his daughter to bed?”

They may not have featured the brutal deaths and graphic sex scenes of Game of Thrones, but those 1960s comics proved formative. As Martin told the BBC: “Maybe Stan Lee is the greatest literary influence on me, even more than Shakespeare or Tolkien.”

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