A British band of the mid-70's. Came out of the Canterbury floating crap game, an incestuously intertwined network of musicians that started (more or less) with Wilde Flowers (which quickly morphed into Soft Machine) in about 1967.
The Canterbury scene produced a good fraction of what's good about art-rock (no, I'm not ashamed to say it), including National Health, Khan, Matching Mole (a bilingual pun on Soft Machine), Gong and all its subsequent incarnations, Bruford (the band, not the drummer), and some others I'm forgetting.
Anyway, the Hatfields are one of my favorite bands from this scene. If you like Lawn Boy by Phish, you'll probably like Hatfield and the North. By the way, their name comes from a highway sign somewhere near London.
There's a gnarly family tree of the Canterbury bands, by Pete Frame, in the vinyl version of Soft Machine's Triple Echo album. Good luck finding a copy.