Quick Links
The Starks are yet to declare for Blacks in the Dance of the Dragons, butHouse of the Dragon- Season 1 clearly states that they are not oathbreakers. Queen Rhaenyra Targaryen wishes to know her allies before declaring war on the Greens and to that end, sends her heir, Prince Jacaerys Velaryon, to the Vale of Arryn and Winterfell. She also sends her secondborn Prince Lucerys to the Baratheon seat of Storm’s End.
Jacaerys sets off on the diplomatic mission on dragonback, and the finale concludes with Prince Lucerys and Arrax’s deaths caused byPrince Aemond Targaryen atop Vhagarin the fight above Shipbreaker Bay. The Eyrie and Winterfell are a long flight from Dragonstone, and Prince Jacaerys is due to arrive in the North inHouse of the Dragon- Season 2. There is talk of the Pact of Ice and Fire between Starks and Targaryens, but what’s it got to do with the Dance of the Dragons?

The Dance Of The Dragons: Prince Jacaerys Velaryon’s Arrival At Winterfell
Before leaving, Queen Rhaenyra informs Jacaerys that the current Lord of Winterfell is his age and likely to find common ground with him:
Cregan Stark is close to your age than is mine. I would hope, that as men, you’re able to find some common interest.

Jacaerys becomes close friends withthe young Lord Cregan Stark, who understands the Blacks' cause as, a while ago, his regent uncle, Bennard Stark, had refused to vacate the seat of Winterfell when he came of age. The young lord had to imprison his uncle and cousins, therefore he was no stranger to the reluctance of relatives to relinquish power. Cregan comes of age in 124 AC, takes the reins in 126 AC, and marries a childhood friend, Lady Arra Norrey in 128 AC. She dies in childbed, leaving behind a son, whom Cregan names after his late father, Lord Rickon.
The Dance of the Dragons breaks out in 129 AC, and Cregan doesn’t break faith with Princess Rhaenyra.Fire & Bloodlore says thatthe Targaryen-Velaryonprince, Jace, reminds the Stark lord of his late brother. The young men hunt, drink, and swear an oath. Prince Jacaerys and Cregan are spotted at the Wall in theHouse of the DragonSeason 2 Official Black Trailer. It is here that the Targaryen prince comments:

The realm will soon tear itself apart if men do not remember the oaths sworn to King Viserys and to his rightful heir.
Jacaerys And Sara Snow
Does Jacaerys Marry Sara Snow?
The court jester, Mushroom (who allegedly kept a record of the events during King Viserys, Aegon II, Rhaenyra, and Aegon III’s time) says that the lateLord Rickon Stark of Winterfellhad a bastard daughter named, Sara.Prince Jacaerys Velaryon allegedly fell in love with Sara during his stay at Winterfell, and they shared a bed. Mushroom’s Testimony claims that Cregan didn’t take this well, but his half-sister quietened him down by saying she had wed the Jacaerys before the old gods at the Godswood of Winterfell.
Archmaester Gyldayn questions the veracity of Mushroom’s claim about Sara Snow and doubts her existence in the first place.The famed writer, Gyldayn, calls Mushroom’s claims “fevered imaginings” and asserts that breaking betrothal to Lady Baela Targaryen was not Jacaerys Velaryon’s way. While Gyldayn finds it “preposterous” that the Targaryen Prince and Queen Rhaenyra’s heir would wed a Stark bastard, he admits to the possibility of Jacaerys and Sara Snow sleeping together.

The Lord of Winterfell during the Dance of the Dragons: Cregan Stark (Tom Taylor in House of the Dragon)
Aliases
The Wolf of the North, The Wolf of Winterfell, The Old Man of the North, The Hand of the Uncrowned King
108 AC
Lord Rickon Stark
Siblings
A younger brother who died in 119 AC A bastard Half-sister Sara Snow (Unconfirmed)
Inherited lordship
Inherited at the age of thirteen in 121 AC
Regency
Bennard Stark who ruled as Regent from 121 AC to 126 AC
124 AC
Took up the rule of the North
126 AC
The Dance of the Dragons breakout
131 AC
What Is The Pact Of Ice And Fire?
Notwithstanding the salacious stories, Cregan Stark of Winterfell and Prince Jacaerys come to an agreement that the Grand Maester of the Seven Kingdoms, Munkun, calls the Pact of Ice and Fire.According to this pact, Jacaerys' future firstborn daughter would marry Cregan’s firstborn, Rickon. The Pact of Ice and Fire cements the most formidable and long-lasting alliance that outlasts Prince Jacaerys and his mother, Queen Rhaenyra’s lives.House Stark formally allies itself with House Targaryenin the Dance of the Dragons and by so doing, Jacaerys secures a major diplomatic victory for the Blacks because no one is as trustworthy and loyal as the Starks.
This agreement reached between Cregan Stark and Prince Jacaerys doesn’t come into force because Jacaerys dies without heirs. He and Vermax are killed inthe Battle of the Gullet, while Cregan Stark keeps his promise and marches to King’s Landing in the final phase of the civil war, in 131 AC. The six days, known asthe Hour of the Wolfby Munkun, are when Lord Stark dispenses justice and passes sentences from the Red Keep. He governs the capital in the name of the late Queen Rhaenyra and Daemon’s son, the eleven-year-old, Prince Aegon, also known asAegon the Younger. Cregan sees to it that Aegon the Younger is installed on the Iron Throne. He uses hisValyrian steel Greatsword, Ice,to behead Aegon the Elder’s murderers and those he condemned for various crimes. He takes his Lady, Alysanne Blackwood, to Winterfell within a fortnight of Aegon the Younger’s coronation and passes on the offer to serve him in the capital.
House of the DragonSeason 2 premieres June 16 at 9/8c on HBO and Max.
House of the Dragon
House of the Dragon is HBO’s prequel series to Game of Thrones. Set hundreds of years earlier, the show follows the inner machinations and rivalries of the Targaryen royal family. The show was created by Ryan Condal and George R.R. Martin, and stars Matt Smith, Emma D’Arcy, Rhys Ifans, and Olivia Cooke.