Fed up

Can anyone tell me where the phrase "fed up" comes from? I've found some references to ancient falconry, but it doesn't really explain the phrase's modern-day context.

Presumably from the analogy with having overeaten and feeling unpleasantly full, having "had enough" (really, having had too much).

Dictionary of American Slang: "Since W.W.I, from Brit. slang. Orig. a version of the French 'J'en ai soupé.' In Brit. sl. since c1900. Fig., having a surfeit...." ~rb

There's a British English extension of this, "fed up to the back teeth", giving the image of being so stuffed that the top layer of food hasn't been able to get past there... (VSD)