As early as 1798 , he spent the winter on an island in the Mississippi a short distance downstream from present - day Quincy , Illinois .
Thomas Forsyth became a successful Indian trader in his youth , spending several years living with the Ottawas on Saginaw Bay .
As early as 1798 , Thomas Forsyth spent the winter on an island in the Mississippi a short distance downstream from present - day Quincy , Illinois .
Thomas Forsyth became a successful Indian trader in his youth , spending several years living with the Ottawas on Saginaw Bay .