All of it came pouring out of Brienne then, like black blood from a wound… the voyage down the Trident, dueling Jaime in the woods, the Bloody Mummers, Jaime crying “Sapphires”, Jaime in the tub at Harrenhal with steam rising from his body, the taste of Vargo Hoat’s blood when she bit down on his ear, the bear pit, Jaime leaping down onto the sand, the long ride to King’s Landing, Sansa Stark, the vow she’d sworn to Jaime, the vow she’d sworn to Lady Catelyn, Oathkeeper, Duskendale, Maidenpool, Nimble Dick and Crackclaw and the Whispers, the men she’d killed… “I have to find her,” she finished. “There are others looking, all wanting to capture her and sell her to the queen. I have to find her first. I promised Jaime. Oathkeeper, he named the sword. I have to try to save her… or die in the attempt. - Brienne VI, AFfC
In ASOIAF is Sansa a traditional northerner name or more of a southerner name?
The only other Sansa recorded in ASOIAF is Sansa Stark, the second daughter of Rickon Stark, eldest son of Lord Cregan Stark. (The Old Man of the North, famous for his 1-day rule as Hand of the King after the Dance of the Dragons, and later for his duel with Prince Aemon the Dragonknight.) You can see some info about that Sansa Stark in these posts, although I hope we learn a lot more about her in the upcoming Dunk and Egg story set at Winterfell.
And Joffrey isn’t the only name like that. There are Alysannes across the country. (Although since that was the name of a very popular Targaryen queen, it probably started as a namesake.) Not to mention Alyses and Eleanor/Elinor/Aelinor/Eleyna/Ellyns. There are plenty of Luke/Lucases, tons of Will/Willems, a plethora of Steffons, and many many many Jons and Jeynes. And again, these names are not exclusive to one region, but all over Westeros.
Furthermore, GRRM has said that while he used to follow the writing rule that you should never have more than one character whose names start with the same letter, with the breadth of characters in ASOIAF that simply wasn’t possible – so instead he drew inspiration from English history “where everyone is named Edward or Henry with a Richard here and there.”
Which is not to say that certain names aren’t common in families, and semi-exclusive as well. The Starks are overpopulated with Brandons, Benjens, Rickons, and girls named Ly–a. (I’d say Rickards also, but there are Rickards in the Crownlands, Stormlands, and the Reach too.) The Lannisters have a ton of Lancels, Cer- names, Ja- names, and Ty- names. (But there are also Ty-’s in Westeros with no relation to the Lannisters.) The Freys have all their Walder namesakes… but we can’t forget that Hodor’s real name is Walder. Then there are the muppet Tullys (and even though that’s a joke, they’re pretty exclusive names). And of course the Targaryens have their Ae-/Rhae-/-On/-Rys names, but there are namesakes in other families too. (Particularly among the Freys.) So even these semi-exclusive names are not without exceptions.
Basically, what I’m saying is that GRRM is not that specific when it comes to worldbuilding with first names. He’ll do some family-style names, but he’s not precise when it comes to north vs south or even region by region. (Though he’s pretty good with distinguishing peasant-sounding names and wildling-type names.) Probably originally most first names were regionally/ethnically exclusive, but by now, Westeros is so multi-cultural that such names are exceptional.
Anyway. The fact that only other Sansa in Westeros (that we know of) was also a Stark probably means our Sansa was named for her. (Like Arya was almost certainly named after her great-grandmother Arya Flint.) And maybe there were previous Sansa Starks that haven’t been mentioned in ASOIAF yet. But for all we know, there could have been several (or plenty) Sansas elsewhere in Westeros. Maybe it’s a Riverlander name too (compare Minisa, Lysa). Or maybe it could be a name from the Reach, as the first Sansa Stark’s mother was from House Manderly, who used to live in the Reach a thousand years back (and Sansa’s sister Serena sounds to me like it could be a Manderly name). Or maybe like some other names, Sansa is common to all of Westeros, if not nearly as common a name as Jeyne or Alysanne.
So… the tl;dr answer to your question is that Sansa is probably a northerner name, if such a thing even exists, or maybe even a traditional Stark name. But we might learn otherwise.
Jon Snow breaks my heart. This boy thought he was so worthless that the only way his life could ever mean anything was if he gave it up and joined the Nights Watch. All his life he never felt like he fit in with his family because he was always known as a Bastard. His whole life he felt alone even though he was surrounded by people that he loved and who loved him. He fell in love with a girl who was an outsider like him to the people of Westeros. She was killed by someone who was supposed to be like his brother. She died in his arms and he held her and tried to make her last few moments comforting and make her not feel so alone in the world. He was murdered by his brothers on the watch. When he died no one held him, he was alone and they let him bleed out and die alone. He never knew his mother or of her. When he was brought back he wasn’t angry he was just heartbroken. The line “I did what I thought was right and I got murdered for it” broke my heart. He forgave the lords who didn’t side with him in a battle he could’ve lost. He forgave them even though he had every right not to. And just Jon Snow breaks my heart and I love him so much.
I’ve been drawing lots of stars and scifi and more stars, so for a change, I finished up an old fanart of Sansa. The idea was to show both her identities; Alayne Stone and Sansa Stark.
Very much lost touch with the show (or rather, ignoring it while being bitter) but can’t wait for the next book to fall from the heavens!