Ozawindib ("Yellow Head") and other Ojibwe guide Henry Rowe Schoolcraft as he maps the source of the Mississippi River. He calls the lake where the great river begins "Itasca."
Why Itasca?
Schoolcraft combines parts of two latin words, "verITAS" (truth) and "CAput" (head), for the true source of the river.
Ozawindib notes that the Ojibwe name for the lake was "Omushkos," meaning "elk."
Adventure Online
Read more about Itasca on this page from Minnesota Place Names.
Investigate Further
Page through William Watts Folwell's A History of Minnesota (4 Volumes). (Minnesota Historical Society Press, 1956)