Hernando de Soto Profession: Spanish Explorer and Conquistador Nationality: Spanish Biography: Led the first European expedition deep into the territory of the modern-day United States, and the first documented to have crossed the Mississippi River. Birthplace: Barcarrota or Badajoz, Extremadura, Spain Died: May 21, 1542 Cause of Death: Fever Articles and Photos Hernando de Soto's Expedition lands in Florida Spanish explorer Hernando de Soto lands on the coast of Florida, somewhere between present-day Tampa Bay and Charlotte HarborMay 30, 1539 Historical Events 1539-05-30 Spanish explorer Hernando de Soto's expedition of 10 ships and 700 men lands in Florida 1539-06-03 Spanish conquistador Hernando De Soto claims Florida for Spain 1540-06-03 Spanish conquistador Hernando de Soto crosses the Appalachian Mountains, 1st European to do so 1541-05-08 Spanish explorer Hernando de Soto and his expedition discover the Mississippi River Famous Conquistadors Diego de Almagro Francisco Vázquez de Coronado Juan Ponce de León Famous Explorers David Livingstone Henry Morton Stanley Robert McClure