...ndians, set out for the present site of Chicago, and by way of the Illinois River reached the Mississippi, Feb. 6, 1682. He descended its stream, and on April 9, 1682, standing on the shores of the Gulf of Mexico , solemnly proclaimed to his companions and to the wilderness that, in the name of Louis the Great, he took possession of the Great Valley watered by the Mississippi River. He set up a column, and i...