On July 25, 1824, the Congress of Gran Colombia issued a law of territorial division intending to include the Canton of Quijos in the Pichincha Province of the Department of Quito, according to the limits it had at the time of creation as the Viceroyalty of New Granada.

The Peruvian refusal to give up the territories escalated tensions between the two countries, culminating in the Gran Colombia–Peru War.

Due to a law made effective on November 21, 1832, Maynas was integrated into the territory of the new Peruvian department of Amazonas, from which it separated in 1853, when a political government was created in the Loreto region.

As of 2005, the Instituto Nacional de Estadística e Informática estimates the province's population to be 536,423.

Persons originating from other regions of the country make up 8.4% of the population and 0.3% of residents were born abroad.