It's been a long time, Game of Thrones fans. Since Season 6 finished airing over a year ago, details both big and small have likely disappeared from fans' memory of Westeros and its perpetually bloody goings-on. So, how did Cersei end up on the Iron Throne in GoT? It's been a long road for her, to say the least — so, let's recap.
When we first met her back in Season 1, Cersei's husband Robert Baratheon was king. It wasn't far into the series before she colluded with the Lannister cousin she was sleeping with at the time to spike Robert's wine during a hunting trip — leading to the "accident" that ultimately killed him. From there, her eldest (and most terrible) son, Joffrey, ascended the throne and was generally an awful ruler. Impulsive, dishonorable, and abusive, he quickly made enemies — and said enemies hatched a complex plan to poison the guy during his wedding reception. It's worth noting that one of the chief proponents of his murder plan was his bride Margaery Tyrell's own grandmother, Olenna Tyrell — because in addition to being a keen political player, she did not want her granddaughter to marry a monster.
After Joffrey's death, Cersei's younger son Tommen became king — and since he was much younger/not nearly as much of a dick, Cersei thought she would have more power acting as his Queen Regent — until Tommen fell hard for the aforementioned Margaery Tyrell. In quite the power move, Margaery slowly turned Tommen against his mother — so Cersei decided to exorcise her hate of the Margaery and the rest of the Tyrell clan by giving power to the High Sparrow. We all remember what happened after that, right? She granted the Sparrow too much power, ultimately leading to her literal walk of shame through King's Landing.
With revenge sorely needed for both the Tyrells and the High Sparrow and the army she gave him, Cersei began to hatch a new plan. A new plan, which you'll remember, hinged on the fact that Robert's predecessor (and Daenerys' dad) Mad King Aerys had stashed cachets of wildfire all over King's Landing. You'll also remember that, back in the day, it was to stop this very plan that Jaime Lannister earned his Kingslayer moniker (but more on that later). On the morning of the day she was actually supposed to be on trial by the High Sparrow, she lit up the entire castle and surrounding areas like a Roman candle, killing everyone at her trial and thousands of innocent civilians in the process.
After his mother murdered his beloved wife (and all their friends), young Tommen removed his crown, and stepped out of his window, falling to his death. And not long after, in full mourning black, Cersei ascended the Iron Throne, as Jaime looked on in disbelief, leading many to believe that the show's paving the way for the "valonqar" portion of Cersei's prophecy to finally come true. That's where we left her at the end of Season 6 — on the throne, enemies and all three children dead, with Qyburn and the zombified Mountain as her only remaining allies.
Cersei's methods for at last becoming queen of the Seven Kingdoms have been far from orthodox. If we track it, she's gone from Queen Consort, to Queen Regent, to just plain Queen — it's not your standard line of succession, that's for sure. No, Cersei seems to be playing from the Richard III playbook — aka kill all your enemies and grab the throne before anyone can say boo. And as with Richard, her method for grabbing power is sure to come back and haunt her (perhaps even literally, as in Shakespeare's telling of Richard's reign). As it stands now, we've already seen her many enemies joining forces against her, perhaps most notably the bereaved and rightfully furious Olenna Tyrell, who went Team Targaryen along with the Dornish Sand Snakes, Tyrion Lannister, and Theon and Yara Greyjoy, to name a few.
Though Game of Thrones was inspired by the very same War of the Roses that inspired Shakespeare's Richard III, George R. R. Martin's never been one to play by the book. While it may finally be coming time for that famous prophecy about Cersei to come true, lord knows he loves subverting our expectations — so who knows what will happen next for our newly minted Lannister queen?