A Song of Ice and Fire

Where does the Game of Thrones Slot Game ultimately come from?
Well, it's all thanks to George R. R. Martin amd his series of fantasy novels called "A Song of Ice and Fire".

The first of the series is called "A Game of Thrones", and was published in 1996. Martin has subsequently built the epic out to 7 volumes, (A Dance with Dragons his 5th took nearly 5 years to write and was published in 2011. The rumours are that Martin will eventually build the series out to eight and his 6th work, The Winds of Winter, is being written as we write this.

"A Song of Ice and Fire" all takes place on the continents of Westeros and Essos. The story is told from various character's points of view - this begins with 9 in the 1st, but builds up to 31 by the 5th novel.

The action unfolds along 3 main storylines: a family war of power in Westeros; the impending threat of the superhuman "Others" on the other side Westeros' northern border; and the fierce ambition of Daenerys Targaryen, a noble daughter in exile, whose soul burns to reclaim her right to the throne.

The story was inspired by the Wars of the Roses, and the French  novels The Accursed Kings.

The books have sold more than 24 million copies in North America and have been translated into more than 20 languages. 

The Books

1 A Game of Thrones 1996
2 A Clash of Kings 1999
3 A Storm of Swords 2000
4 A Feast for Crows 2005
5 A Dance with Dragons 2011
6 The Winds of Winter (to be released)
7 A Dream of Spring 9to be released)
 

Sales

Reuters reported in 2013 that the books (print, digital and audio) have sold more than 24 million copies in North America.
Forbes estimated that Martin was the 12th highest-earning author in the world in 2011 at $15 million. That figure has increased substantially following the string of licensing deals that have been agreed with various arties, including the Game of Thrones Slot by HBO and Microgaming.