The Jesuits founded Iquitos in 1757 under the name of San Pablo de los Napeanos. It was the first port on the Amazon River. As in the case of many other towns founded in the Region during the 18th Century, Iquitos was the point from which evangelists began preaching their religion to the native people of the area.
Until approximately 1870, the city's population was less than 2,000 inhabitants. However, in only 10 years, Iquitos exceeded 10,000 inhabitants. In 1880, hundreds of people migrated to this place, attracted by the rubber boom. At the beginning of the 20th century, the city and river port became well known in international markets, which fostered the incorporation of a large number of foreign companies, as well as the presence of Spaniards, Italians, Portuguese and Germans. The opulence of those days is still noticeable in some of the city's buildings.

In 1971, oil exploitation was begun together with several projects for the use of forest resources. Surrounded by the best preserved forests due to its geographic isolation, the Iquitos Region shows features inherent to the Amazon eco-system and native groups which, in contact with civilization, live mainly on the banks of the Amazon, Napo, Ucayali, Marañón and Nanay Rivers.

This part of the Peruvian Amazon Region is home to one of the largest hydrographic system in the world, the Amazon Basin, which begins in the Andes Mountain Range (Arequipa) where the Amazon River is born, the river with the largest volume of water in the world. It is formed by the confluence of the Ucayali and Marañón Rivers, close to the City of Nauta.