What county is Dartmouth, MA located in?

I'm looking at different colleges around Massachusetts and noticed there are a bunch of campuses and towns with similar names. I came across Dartmouth, MA (where UMass Dartmouth is), but I can't figure out exactly which county it's in by just Googling quickly.

Is it in Bristol County or somewhere else? I feel like this might matter for residency stuff or when filling out applications. Anyone from the area (or who applied to schools around there) know for sure?