HBO’s Game of Thrones is a dense series with a huge weight of history behind its story, so in practically every episode, something happens that could use a little explanation. So every week, The Verge will be diving into a scene or event from the latest installment of the series and explain how we got here. Whether you’re basically a Game of Thrones maester or you need a little reminder about previous events, we’ll try to help you keep your history straight.

Game of Thrones is finally back, and it’s pretty clear that winter is finally here. But the most important event in the premiere episode, “Dragonstone,” didn’t take place in the swirling, zombie-filled snows of the North, but in the South, on the eponymous island that gives the episode its name.

Spoilers ahead for Game of Thrones season 7, episode 1

Daenerys takes Dragonstone

The episode’s final sequence is significant because after six seasons of gathering armies, forging alliances, murdering or exiling traitors, and raising dragons, Daenerys Stormborn of the House Targaryen, First of Her Name, the Unburnt, Queen of the Andals and the First Men, Khaleesi of the Great Grass Sea, Breaker of Chains, and Mother of Dragons, has finally landed in Westeros. Dragonstone is her ancestral home, and by returning there, Daenerys has instantly changed the balance of power in Westeros.

Taking Dragonstone from Stannis

Stannis Baratheon, the younger brother of King Robert Baratheon, left Dragonstone unguarded at the end of season 3. He was pursuing a campaign to oust the Lannisters and take the Iron Throne when his advisor Melisandre convinced him that as the chosen one of the Lord of Light, he needed to follow his true destiny and pursue the real war against the White Walkers in the North. Stannis, never one to do things by halves, fully committed to the cause, pulling every one of his followers out of Dragonstone, which is why Daenerys finds it empty and unguarded. Robert had given Stannis rule over Dragonstone as a reward for taking it during Robert’s Rebellion. Stannis built a fleet to capture the island, the last Targaryen stronghold holding out against the rebel soldiers. Daenerys reclaiming Dragonstone returns it to Targaryen hands.

Dragonstone has been the seat of House Targaryen for centuries

Dany’s return is historically important because Dragonstone belonged to her family, dating back hundreds of years, before the fall of Valyria in an unknown magical cataclysm that shattered the empire. The Targaryens, a minor house by Valyrian standards, fled to Dragonstone and managed to avoid the doom of the rest of the Valyrian Freehold. Aegon Targaryen, also known as Aegon the Conqueror, used his family’s dragons to conquer the mainland of Westeros and become the first ruler of the Seven Kingdoms. His dynasty lasted until Robert’s Rebellion usurped the throne from its Targaryen rulers. Dragonstone remained the ancestral seat of the Targaryens during their rise and reign, until the last two remaining children — Daenerys and Viserys — were smuggled off the island before Stannis’ conquest.

Daenerys is back — and she’s got dragons

Now, much like Aegon the Conqueror before her, Daenerys is in Dragonstone with her eye on conquering the Seven Kingdoms. And like her many-greats-grandfather, she has the literal firepower to back her claim. It’s worth noting that Daenerys ignored the throne at Dragonstone, and proceeded directly to the campaign room behind it. After years of sidetracking and spinning her wheels, Daenerys has arrived in Westeros, and she’s got her eyes firmly set on the Iron Throne.

Learning Game of Thrones theme song on a futuristic keyboard