From Variety's reading of GRRM's original 1993 pitch of "A Song of Ice and Fire" :

Ned and Catelyn Stark were always doomed. In Martin’s pitch, Ned’s death is conceived almost exactly as it plays out in the book and TV show; he discovers the truth about Jon Arryn’s murder, and after his friend King Robert Baratheon dies, is accused of treason and sentenced to death by Robert’s sadistic heir, Joffrey. The main difference in Martin’s original plan is that before Ned’s death, he helps Catelyn and Arya escape King’s Landing and return to Winterfell. In the book and show, Catelyn is already out of the city at the time of Ned’s execution, although his quick thinking does save Arya — but neither surviving Stark is able to find safety at Winterfell following Ned’s murder.

Sansa Stark was going to marry Joffrey — and have his son and heir. Martin writes that when push comes to shove, Sansa “will choose her husband and child over her parents and siblings, a choice she will later bitterly rue.” Thankfully, she ends up dodging that bullet in the show and novels when Margaery Tyrell enters the picture and becomes the boy-king’s bride, and Joffrey subsequently dies childless after being poisoned at their wedding.

Joffrey was supposed to fight Robb Stark. Martin held true to his plan for Ned’s death to incite a war between the houses, but in his original pitch, Joffrey actually faces Robb on the battlefield (and ends up maimed for his trouble). Robb is then defeated by Joffrey’s uncles, Jaime and Tyrion Lannister, and dies in battle, allowing Tyrion to “besiege and burn down Winterfell.” There’s not a hint of the Red Wedding to be found in Martin’s letter, for better or worse.

Jon Snow and Arya fell in love. It seems especially disturbing given the age difference of the actors on the show, but Martin originally intended for the half-siblings to fall for each other, ending up “tormented” by their passion throughout the trilogy because of Jon’s vows of celibacy to the Night’s Watch — at least “until the secret of Jon’s true parentage is finally revealed in the last book.” Jon is also forced to turn away Catelyn, Arya and brother Bran when they arrive at The Wall following the destruction of Winterfell, prompting them to flee further North, beyond the Wall, where they’re captured by Mance Rayder and encounter the supernatural Others. “Bran’s magic, Arya’s Needle and the savagery of their Direwolves will help them survive,” writes Martin, “but their mother Catelyn will die at the hands of the Others.” Somehow, that still sounds less traumatic than how her death played out on-screen. Bran’s trajectory seems to stick fairly closely to Martin’s pitch, since he loses his ability to walk and turns to magic at first to try and heal himself, “but later for its own sake.” He also has prophetic dreams, but is unable to prevent any of the catastrophes that befall his family.

Tyrion also fell for Arya. After “removing” Joffrey from the throne out of disgust for his nephew’s antics (thereby clearing the way for Jaime to succeed Joffrey on the throne, after Jaime kills everyone else who has a claim and blames Tyrion for their murders) the Imp is exiled and switches sides, aligning himself with the Starks to “bring his brother down, and falling helplessly in love with Arya Stark while he’s at it,” Martin writes. This leads him into a rivalry with Jon, although Arya doesn’t return Tyrion’s affections. In “A Song of Ice and Fire” and the show, it’s Sansa that Tyrion grows closer to, and after being accused of killing Joffrey and murdering his father, Tywin, Tyrion escapes King’s Landing and seems to be set to cross paths with Daenerys Targaryen instead of the Starks.

Daenerys invaded Westeros a lot sooner — after killing her husband. Khal Drogo does dispatch Dany’s brother, Viserys, but in Martin’s original plan, she resents him for it, and bides her time until she can kill Drogo in vengeance. Then she flees into the wilderness, where she discovers three dragon eggs that will allow her to invade the Seven Kingdoms. Her return to Westeros was intended to be the focus of the second volume in Martin’s trilogy, “A Dance with Dragons,” while the war against the Others and a climactic final battle at the Wall would’ve form the basis for Martin’s last novel, “The Winds of Winter.”

Five characters were designed to survive all three books. It should come as no surprise given these breakdowns and the perspectives of Martin’s published books, but Daenerys, Arya, Jon, Bran and Tyrion are the five POV characters that Martin initially intended to follow all the way through the story, “growing from children to adults and changing themselves and the world in the process. In a sense, my trilogy is almost a generational saga, telling the life stories of these five characters,” he writes in his 1993 letter. Whether “A Song of Ice and Fire” will follow this original outline remains to be seen (and could be called into question by the events of what became Martin’s fifth book, “A Dance with Dragons.”) Ultimately, the only way to find out is to keep reading — or watching.

A lot can change in 22 years so we cannot take any of these as being what happens.

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