While leading the first European expedition deep into the territory of the modern-day United States, de Soto was the first to have discovered the Mississippi River. His expedition ranged throughout the southeastern United States searching for gold and a passage to China.
Editors. "Expedition into North America by Hernando de Soto". The Literary Encyclopedia. First published 01 January 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=10024, accessed 30 August 2016.]