Marañón River

In what is currently in Brazil, Ecuador, Bolivia, Colombia, Peru, and Venezuela, several colonial and religious settlements were established along the

banks of primary rivers and tributaries for trade, slaving and evangelization among the indigenous peoples of the vast rainforest, such as the Urarina.

In the late 1600s, Czech Jesuit Father Samuel Fritz, an apostle of the Omagus established some forty mission villages. Fritz proposed that the

Marañón River must be the source of the Amazon, noting on his 1707 map that the Marañón “has its source on the southern shore of a lake that is called Lauricocha, near Huánuco.” Fritz reasoned that the Marañón is the largest river branch one

encounters when journeying upstream, and lies farther to the west than any other tributary of the Amazon. For most of the 18th–19th centuries and into the 20th century, the Marañón was generally considered the source of the Amazon.[28]