Unless you've read A Song of Ice and Fire, you probably weren't totally sure what was going on all the time on Game of Thrones, or what in the Seven Hells some of the characters were talking about when discussing historical events. Even if you read the books very carefully, you could still find yourself reeling; Game of Thrones history is just that dense.
For example, did you know that Robert Baratheon and Ned Stark grew up together as wards of Jon Arryn? Do you know why Daenerys named one of her dragons Rhaegal? Do you know who broke up Tyrion's first marriage? And why does Littlefinger seem to hate everybody? All of these tidbits come from events that occurred before the show even starts!
Fear not! This list is here to quickly fill you in on the most important backstories - some recent, some going back 8,000 years - that inform the events of Game of Thrones. Some are very recent, while others go back 8,000 years.
Ask any follower of R’hllor and you’ll get the lowdown on Azor Ahai. He was the hero that brought about the generation-spanning Long Night, occurring during the Age of Heroes around 8,000 years before Aegon’s Conquest. If you got Old Nan wound up, she’d tell you of the never-ending darkness where the cold killed kings in their castles and mothers killed their children to end their suffering as the Others rode upon their dead horses killing everyone in their frosty wake.
Wielding his sword Lightbringer (forged through the heart of his beloved wife Nissa Nissa), Azor Ahai lead brave men and women to fight the Others and drive them back to the Land of Always Winter. A second coming of the Long Night is nigh, so this needs yet another Azor Ahai. Many speculate that the role will fall to Jon Snow with the help of his aunt Daenerys. Others speculate that the hero will be Dany. Aegon Targaryen thought HE was the guy. In any case, a happy ending is not guaranteed as the prophecy states that if the hero fails, the world ends. Womp womp.
This explains the obsession the followers of the Lord of Light have with finding the one true Azor Ahai. He or she is also known by other names in other cultures such as Yin Tar, Neferion, Eldric Shadowchaser, Hyrkoon the Hero, and Help! Come Save Me! A Wight Is Eating My Face!
The books are getting there, but Game of Thrones revealed that the Children created the White Walkers to fight the First Men by sacrificing a First Man at their ancient weirwood tree beyond what is now the Wall. They ran a dragonglass dagger into his heart and created an unstoppable monster. Well, sh*t.
Leaf and the Children turned to Bran for help to defeat the nuclear bomb of death they had created in their weirwood lab. He’s going to need all of the able-bodied heroes the world can provide because his rogue warging has already done some damage. The Night King was able to mark him.
Before they devolved into infighting and insanity, the white-haired and purple-eyed Targaryens were the most powerful house in Westeros. They owed that status to Aegon I Targaryen and his two sisters/wives, Rhaenys and Visenya, who united six of the seven existing kingdoms (Dorne just wouldn't cooperate). They used dragons to make all the other kings "bend the knee." The year of Aegon's conquest is Year Zero as far as the Westerosi calendar is concerned.
Elia Martell (sister of Oberyn) was a Dornish princess who married the Crown Prince Rhaegar Targaryen. They had two children before her womb stopped working. When Rhaegar won a tournament at Harrenhal, he chose Lyanna Stark as the Queen of Love and Beauty instead of his own wife.
During the sack of King's Landing, Elia Martell was raped and murdered by the Mountain, Gregor Clegane. He also smashed her babies (Rhaenys and Aegon).The Dornish were already suspicious of the Iron Throne and craving their independence. After Elia's unhappy life, they really hate being ruled by King's Landing.