Game Of Thrones Season 8: 12 Things You Might've Missed In 'A Knight Of The Seven Kingdoms'
9. Targaryens Coming North
In this week's episode, Tyrion makes a remark about the North remembering what happened the last time a Targaryen brought dragons North. It's offhand and not followed-up on, but what exactly does he mean?
The last time a Targaryen brought a dragon north was Beyond the Wall, when Dany went to rescue Jon et al, and Viserion ended up dead. But that was a Targaryen, not Targaryens.
During Aegon's conquest, the King in the North, Torrhen Stark, marched his banners to meet Aegon and ended up kneeling to him, but that event didn't occur in the North. After that, there aren't many instances of Targaryens or their dragons paying a visit. Aegon did so on his last progress through the Seven Kingdoms; Jaehaerys I did so with around six dragons, but he was popular; and Jacaerys Velaryon did so on Vermax, making the Pact of Ice and Fire with Lord Creggan Stark.
There are theories abounding regarding dragons laying eggs at Winterfell and such like, but there's nothing in there that would suggest anything bad to remember, nor anyone old enough to remember it, as Tyrion's words suggest, so perhaps it's just poorly worded.