LaSalle explored the Mississippi Valley and brought the plains west of the river to Europe’s attention. From Texas to Illinois he pioneered settlement. Francis Parkman considered him to be so important that he devoted an entire volume of his epic series of books The French in North America to him.
"The discovery of the "Great West," or the valleys of the Mississippi and the Lakes, is a portion of our history hitherto very obscure. Those magnificent regions were revealed to the world through a series of daring enterprises, of which the motives and even the incidents have been but partially and superficially known. The chief actor in them wrote much, but printed nothing; and the published writings of his associates stand woefully in need of interpretation from the unpublished documents which exist, but which have not heretofore been used as material for history.
This volume attempts to supply the defect."
From LaSalle and the Discovery of the Great West http://dld.bz/heVSz
Francis Parkman’s series of books on the French in North America http://dld.bz/heARQ