In the decades following the initial European discovery of the "West Indies" and the Americas, countless expeditions were launched into the interiors of these regions. The stated goals were often the same that drove the initial voyages: to find an easier water passage to Asia, to spread the word of Christianity, and to discover new sources of wealth. Especially regarding the latter motivation, the role of legend and myth came to provide a major catalyst.

In South America, for example, rumors spread of a golden empire so wealthy that the king covered himself with fresh gold dust every day rather than simply wear gold adornments like other kings. This legend of "El Dorado" compelled many to seek their fortunes in exploring the interior. From one such expedition launched from Quito (in modern-day Ecuador), Spanish soldier and explorer Francisco Orellana's smaller party departed and explored the...