The Game of Thrones season 6 finale confirmed what fans have practically known for years: That Jon Snow is no son of Ned Stark’s. Instead, he’s the child of Rhaegar Targaryen and Lyanna Stark, his parenthood kept a secret to save the boy’s life from Ned’s own best friend, Robert Baratheon. He was born because Rhaegar was trying to fulfill prophecies that the prince that was promised would come from his father’s line, and that “the dragon must have three heads.” And it was no accident that Rhaegar chose Lyanna—for the Starks had never before intermarried with the Targaryens. Jon Snow is the first time that ice and fire have met as one.

Jon Snow Is The First Stark And Targaryen Child

The Targaryens ruled Westeros for the better part of three centuries, but the dragon dynasty—like the historical Habsburgs—liked to keep it in the family. Targaryens intermarried only relatively little with the Great Houses of Westeros. Most of the time, Targaryens preferred to marry other Targaryens; next, they leaned toward members of the handful of old Valyrian houses—especially House Velaryon—who had also settled with them along the narrow sea before the fall of Valyria. Only after that would they marry with the other Houses. Over the centuries, the Targaryens eventually crossed with several of the great Houses—notably Baratheon, Martell and Arryn—as well as a handful of lesser houses and others from Essos.

But the Targaryens have never crossed with the Starks—despite a promise after the Hour of the Wolf that a Stark would marry a Targaryen princess, no one of dragon blood has ever married anyone from the North. The closest crossing is Bloodraven, a Targaryen bastard son of Aegon IV and Melissa Blackwood, a member of a Southern house that still worships the old gods and claims descent from the First Men. Bloodraven went on to become an exceptional individual—the three-eyed crow/raven. That’s the sort of power that can seemingly arise when the blood of Valyria and the First Men meet.

It’s unclear whether Rhaegar and Lyanna fell in love (or possibly even married), or whether Rhaegar truly did abduct her. But it’s plenty clear that it was no accident that Lyanna was the target of his affections. Rhaegar lived his life according to prophecies and aimed to do what must be done. And to engender one of the three heads of the dragon—he clearly believed he had to orchestrate the first ever crossing between Stark and Targaryen—between ice and fire.