I watched a couple of videos that theorized that the White Walkers built the Wall and negotiated peace with men. I think the theory first got mentioned here when the Night King first showed up in S4. Now, sometimes, someone tells a Stark that "there must always be a Stark in Winterfell" and I thought it was because they're the only ones who can fight the White Walkers or something. But now that I think about it, I think it's because it might be a condition of the peace negotiations men and the White Walkers had long ago. Either that, or the White Walkers just want to talk to the Starks and no one else.