George R. R. Martin is as rich as any king of Westeros.

A quarter of a century ago now, Martin wrote the first book in his still-unfinished series, A Song of Ice and Fire. Who knew that one day A Game of Thrones, would be turned into HBO's Game of Thrones in 2011? Who knew that the show would end and we'd still get new material from Martin, years later?

The show diverged from the books halfway through its run because Martin's series is still being written. He's currently writing Winds of Winter and has been for years, and it sounds like he been on a roll since quarantine. So we might be returning to Westeros sooner than we thought.

If isolation really has helped him focus, it might be a nice surprise for fans...finally. Either way, with a new book release or the premiere of a Game of Thrones spin-off, Martin's $120 million net worth is sure to skyrocket.

He's Made About $10 Million From His Book Series

Ironically, the first year that A Game of Thrones was released, "America's Tolkien" earned well below par. When HarperCollins published it they expected it to sell a measly 5,000 copies. Martin went on a tour of the U.S. to promote the book's release but turnouts were rough.

Sales of the hardcover book back in 1996 "were … well, OK. Solid. But nothing spectacular. No bestseller lists, certainly," Martin wrote on his blog.

Eventually, with the arrival of more paperback copies, "word-of-mouth recommendation was soon spreading like wildfire around fans. And it wasn’t long before we exceeded all of our original expectations, and soon the series books were all hitting the bestseller lists."

A Game of Thrones was followed by A Clash of Kings in 1999, A Storm of Swords in 2000, and A Feast for Crows in 2005, with the latter seeing a massive increase in sales and the No. 1 spot on The New York Times Bestseller's List as well as The Wall Street Journal's.

This success attracted the attention of Hollywood and in 2007, Martin sold the rights to his series to HBO, who immediately set to work making the series we know and love. Martin was reluctant at first because he didn't think the books would translate to screen but the producers convinced him. Martin had experience working on television after all and knew how it worked.

Related: What The Cast Of 'Game Of Thrones' Is Up To Now

Meanwhile, Martin was still writing the books. Dance with Dragons came in 2011 and was an international bestseller and also occupied New York Times Bestseller List at No. 1. It sat on the list for 88 weeks. Game of Thrones premiered that same year.

A year before Game of Thrones ended on television, Martin half upset, half excited, fans when he released a spin-off book, Fire and Blood in 2018. By that point, fans were already becoming outspoken on how long it was taking Martin to release Winds of Winter, which he's been writing since 2011. It was great that he released another book in between books, but fans wanted Winds of Winter. They still haven't gotten it.

Martin has so far described Winds of Winter as several novels all wrapped up into one, so juggling all these characters and storylines can get confusing. He even has charts to help him keep track of details in the books.

Martin has revealed that he's gotten a lot done in quarantine, saying he's written "hundreds and hundreds of pages" and that "there are days when I sit down in the morning with my cup of coffee, I fall through the page and I wake up and it’s dark outside and my coffee is still next to me, it’s ice-cold and I’ve just spent the day in Westeros."

Related: What Has Peter Dinklage Been Up To Since 'Game Of Thrones'?

"The best year I've had on WOW since I began it." While he's been in Westeros, however, his books have sold 90 million copies and have earned him about $10 million.

He Earns $25 Million A Year

According to Celebrity Net Worth, Martin earns an estimated $25 million a year between book sales and earning $15 million per season, working on Game of Thrones. In total, he earned about $200 million for his contributions as an executive producer and writer on the show. He's written four episodes.

In 2016, Forbes estimated his yearly earnings. In 2012, he received $15 million. His books sold 8 million copies riding the high of the premiere of the show. There was a spike in e-book sales and A Game of Thrones sold $1 million copies in 2013, which earned him $12 million. There was a spike in mass-marketed Game of Thrones paperbacks in 2014, which also earned him $12 million.

In 2015 he also earned $12 million. Print sales waned but Martin still made a lot for his contributions on the show which, by that point, was raking in 20.2 million viewers per week in season five.

Related: The Challenges Kit Harington Dealt With After 'Game Of Thrones'

Martin juggled the show and writing while Game of Thrones was on the air, and he'll likely continue to, as it was announced he'll be working on the five spin-off series' HBO has planned.

Now, after all the success he's had, Martin can hardly believe that his first book, which came to him "out of nowhere," became this huge franchise.

"When I began, I didn’t know what the hell I had. I thought it might be a short story; it was just this chapter, where they find these direwolf pups. Then I started exploring these families and the world started coming alive," Martin said. "It was all there in my head, I couldn’t not write it."

"Like every other young writer, I dreamed of fame and fortune. Having achieved them I can tell you that fortune is great."

Martin enjoys his riches (he gets to donate millions to Wild Spirit Wolf Sanctuary etc. and bought his own cinema) but thinks fame is a double-edged sword. As long as it's not Needle that's doing the sticking. We need him to finish the series after all.

Next: The Cast Of Game Of Thrones, Ranked By Net Worth