Texas
Home state of the Cooper family. Sheldon was born in the Lawrence Memorial Hospital in Galveston (0209), and his mother and sister still live in that area.
Leonard, Raj and Howard fly to Texas after Sheldon resigned at the university and fled home in The Electric Can Opener Fluctuation. Raj is surprised that Texas doesn't look like it did in the movies he watched as a child in India (0301).
As a child growing up in Texas, Sheldon learned all about football from his father, even though he wasn't in the slightest bit interested ("All right, Poindexter, sit down, shut up, and listen.") Didn't matter ... it's Texas, and football is ingrained in the culture. Sheldon commented that the only kind of football Texans don't like is the original, European football, which most Texans believe is a "Commie plot". He told Leonard that he could also teach him other Texas lore, such as "frying meat that isn't chicken as if it were chicken", and later he could teach him how to "shoot close enough to a raccoon that it craps itself" (0306).