Forsyth's manuscript entitled “Manners and Customs of the Sauk and Fox Nations of Indians,” containing accounts of tribal traditions, history, government, religion, customs of war and of peace, family life, medicine, hunting practices, and language. Notations by the author state that a copy was delivered to William Clark in January 1827. Following the manuscript in this volume, however, are other writings and annotations added by Forsyth in subsequent years: place-names of Indian derivation; descriptive data on the Chippewa, Kickapoo, Ottawa, Potawatomi, and Winnebago tribes; a copy of a letter (1812) to Clark discussing the geographic features of Illinois and Indiana, the Shawnee Prophet and the regulations he imposed on his faithful adherents; a discussion of the cause of the Black Hawk War of 1832; a reminiscent anecdote from Forsyth's days as a clerk trading with the Chippewa in Michigan; a short narrative of his visit in October 1832, to an encampment of the segment of Kickapoo governed by the Kickapoo Prophet. On the outer cover of his volume, Forsyth wrote under the title the date of 1832, the year of his final annotations rather than the dates of his earlier compositions.

Includes documents in Sauk and Fox (p. 5, 22, 32-36).