Lighter wrote: Bob, since the Lomax and Gordon texts all mention arrival at an established Pocahontas (originally "Pine City"), the song is unlikely to have been written before 1863 - and it could easily have been written later. (Pocahontas, says Wikipedia, set up a post office on Aug. 4, 1863.)

A very strong argument. :-) But I didn't know. Thanks for the additional information.

Either way, I wouldn't rely too heavily on the identity of the Indians. "Sioux" prominently lived out west, were (or had been) at war with the United States, and the name usefully has only one syllable.

Agreed. But it's worth point out that, no matter what the song says, it probably wasn't actual Dakota. If it happened, it's probably some other nation's fault.