Query: Name of French Explorer

[Justin McBride]

Might it have been the Marquis de Cadillac?  He was a charlatan of the first
order--starting with his title (he was by no means a marquis, and at best
dubiously noble-born).  Supposedly he had many infamous run-ins with the
tribes of the Lake country, although I cannot remember any of them right
now.  I've heard he was generally not well-received in many societies, be
they American or European.  It's pure irony that the automobiles bearing his
name are so highly prized!