de Soto at English => English (The Britannica Concise) Of Explained:
Spanish explorer and conquistador. He joined the 1514 expedition of Pedro Arias Dá vila (1440-1531) to the W. Indies, and in Panama he quickly made his mark as a trader and explorer. By 1520 he had accumulated a small fortune through his slave trading in Nicaragua and on the Isthmus of Panama. He joined F. Pizarro on an expedition to conquer Peru in 1532, returning to Spain in 1536 with great wealth. Commissioned by the Spanish crown to conquer what is now Florida, he departed in 1538 in command of 10 ships and 700 men. On that expedition he explored the extensive region that was to become the SE U.S. and discovered the Mississippi River. Overcome by fever, he died in Louisiana and was buried in the Mississippi.