James and Say's "Sodomy is commonly committed", 1819-20
In his Account of an Expedition from Pittsburgh to the Rocky Mountains in the Years 1819 and '20 ... Edwin James quotes a member of the expedition, T. Say, "who had spent some time among the Konzas," near Omaha, on the Platte and Konzas Rivers.
Sodomy is a crime not uncommonly committed; many of the subjects of it are publicly known, and do not appear to be despised, or to excite disgust; one of them was pointed out to us; he had submitted himself to it, in consequence of a vow he had made to his mystic medicine, which obliged him to change his dress for that of a squaw, to do their work, and to permit his hair to grow.
Later James himself adds of the Omahas:
Among their vices may be enumerated sodomy, onanism, & various other unclean and disgusting practices. What is related of the Illinois by Hennepin, may, with equal truth, be applied to the Omawhaws. But to the honour of humanity, it may be remarked that those abominable traits of character are not generally conspicuous among them.