Walking by Bergritte Battle-Born in Whiterun she said, "Evgir unslaad has come at last. The season unending. War... without end."

It's actually dragon language: evgir = season, unslaad = unending.

I didn't realize Nords still knew the dragon language. Think it's just something that was passed down through the Battle-Born family, this phrase, or is there more to it?

They probably know small phrases, like Dovahkiin, but on the whole only the Greybeards are one of the few groups that can actually speak it.

Huh, never noticed that before. That's pretty interesting.