"Game of Thrones" introduced audiences to the various houses, great and small, that populate the lands in and around Westeros — starting with the Targaryens, Starks, Baratheons and Lannisters. Set almost 200 years before the events of the flagship series, "House of the Dragon," which premiered Sunday on HBO, depicts the distant ancestors of well-known houses and familiarizes viewers with lesser-known clans as they orbit around the Seven Kingdoms' seat of power, the Iron Throne.
At the outset, "House of the Dragon" is primarily focused on members of House Targaryen, the current ruling family, and their closest allies. But the "Game of Thrones" prequel series boasts an expansive cast of characters, often with names that are barely distinct from somebody just as significant. Here's a guide to those we meet in Sunday's premiere and expect to play a key role in the series going forward.
A noble family of Valyrian descent who left their homeland before its collapse. The clan of dragon-riders became the first ruling house of the Seven Kingdoms of Westeros thanks to a successful conquest led by King Aegon Targaryen; the family ruled over Westeros for almost 300 years. In order to keep their bloodlines pure, Targaryens often married their siblings or cousins. ("Game of Thrones" fans know how that played out.) One of the most well-known houses in the franchise, the Targaryens are still prosperous when "House of the Dragon" begins, but peaceful times do not generally translate into eventful television.
Viserys Targaryen (Paddy Considine)
The current ruler of the Seven Kingdoms and the fifth Targaryen king to sit on the Iron Throne. Viserys was chosen by the Great Council to succeed his grandfather, King Jaehaerys Targaryen, over his elder cousin, Princess Rhaenys Targaryen, because he was the king's oldest male descendant.
Daemon Targaryen (Matt Smith)
King Viserys Targaryen's younger brother and presumptive heir — or so he believes. A formidable warrior, Prince Daemon serves as the commander of the City Watch of King's Landing. The prince has his eye on the Iron Throne, but key figures do not believe he's fit to rule.
Rhaenyra Targaryen (young: Milly Alcock, adult: Emma D'Arcy)
King Viserys Targaryen's first-born child, who rides a dragon named Syrax. She has grown up watching her father wish for a son to secure his succession.
Rhaenys Targaryen (Eve Best)
King Jaehaerys Targaryen's grandchild who, as his oldest living descendant, had a claim to the Iron Throne. Since the Great Council passed her over, she has been known as "the Queen Who Never Was." Princess Rhaenys is the cousin of King Viserys Targaryen, who inherited the crown instead. She is married to Lord Corlys Velaryon.
An old and powerful noble house whose ancestral home is in Oldtown — where the Citadel is located — in the region known as the Reach. The Hightowers are known for their wealth and are affiliated with the Tyrells, a house "Game of Thrones" fans are likely more familiar with.
Otto Hightower (Rhys Ifans)
The Hand — or lead advisor — of King Viserys, loyal to both his king and the realm. Ser Otto does not believe Prince Daemon Targaryen is fit to be King Viserys' heir, and their dislike is mutual. Father of Alicent Hightower.
Alicent Hightower (young: Emily Carey, adult: Olivia Cooke)
A close friend of Princess Rhaenyra Targaryen and Ser Otto Hightower's daughter, Alicent grew up in the Red Keep. Described as one of the most attractive women in all of Westeros, she is also said to be close with King Viserys Targaryen.
The Velaryons are a noble house that, like the Targaryens, hail from an old Valyrian bloodline. The influential family is a key ally of House Targaryen, so their prosperity — and family trees — are intertwined. The Velaryons also boast the biggest navy in Westeros. Although House Velaryon is extremely wealthy and powerful during the time of "House of the Dragon," they don't even appear in "Game of Thrones."
Corlys Velaryon (Steve Toussaint)
Westeros' most famous seafaring adventurer, also known as "The Sea Snake." Thanks to Lord Corlys, the Velaryons are a powerful house that is said to be richer than the Lannisters. Lord Corlys is married to Princess Rhaenys Targaryen, and they have two children: Laena and Laenor Velaryon.