The Portuguese conquest of Maranhão took place between 23 August 1612 and 3 November 1615, in the state of Maranhão, Brazil, between Portuguese and Tabajara forces, on the one hand, and French and Tupinambá forces, on the other. The campaign resulted in the definitive expulsion of the French from Maranhão on November 4, 1615.
The expulsion of the French allowed a large part of the Amazon to fall under Portuguese dominion.
Background
The French had previously tried to establish a colony Brazil, France Antarctique, until they were defeated by Portugal in 1567.
In 1611, French regent Maria de Médici provided further instructions for the establishment of a new colony in Maranhão.<ref name="cardoso">Alírio Cardoso: The conquest of Maranhão and Atlantic disputes in the geopolitics of the Iberian Union (1596-1626)" in Revista Brasileira de História, São Paulo, volume 31, nº 61, p. 317-338 - 2011, p. 326.</ref> In March 1612 a fleet of three ships and 500 men set sail from Cancale in Brattany, stopping at Fernando de Noronha before making a landfall in Brazil. The French established a colony in Maranhão, with the support of local indigenous people: on September 8, the village of Saint Louis was founded and the construction of the Fort Saint Louis began on top of a hill in front of the sea, in a region claimed by Portugal. In 1613 Daniel de La Touche had fort Itapery built in modern-day São José de Ribamar
Aware of the presence of the French in the north of Maranhão, the governor-general of Brazil Gaspar de Sousa organized in Pernambuco an expedition to conquer the area from the French. On August 23, 1614, serjeant-major Diogo de Campos left Recife with 300 men and in Rio Grande do Norte joined captain-general Jerónimo de Albuquerque, who was accompanied by a large contingent of indigenous auxiliaries. The Portuguese expedition with 500 men led by Albuquerque camped on the mouth of the Periá River looking for a place to build a fortification. They faced a shortage of food and fresh water. A group of 14 Portuguese scouts discovered a suitable place for the fort and the expedition set sail again on October 2, 1614.
On October 26, they reached an area called Guaxindubá by the natives, on the right bank of the Bay of São José, among many islands and narrow channels. A hexagon-shaped fortification was built on the beach of Guaxenduba under the guidance of engineer Francisco Frias de Mesquita, and named Santa Maria, about 20 km from the current seat of the municipality of Icatu, within sight of the French fort Itapary.
Once established, the Portuguese set to work building and keeping guard of their fort while conducting the reconnaissance of the region. Some natives whom the Portuguese contacted claimed that the island was full of French, while others claimed that the French had left.
On October 30, a group of indigenous people from the island killed four women of the natives who were accompanying the Portuguese. This caused them to become suspicious of the natives and believe that they had been sent by the French to spy on their ships. Through a Tupinamba prisoner made by Mandiocapuba Azevedo became aware of the strength of the French. On the final days of October, the Portuguese at the fort Santa Maria and on the island of Santana observed the movement of French ships in the Bay of São José and the landing of artillery pieces.
First French attack
On November 10, 1614, the sergeant-major Diogo de Campos sent a group of sailors to defend the vessels that were anchored or stranded in the estuary after arguing with Jerónimo de Albuquerque, ordering that they remain vigilant. At dawn on 11 November, the French, guided by Monsieur de Pézieux, Monsieur du Prat and François Rasilly, approached the ships silently. When the Portuguese became aware of the attack, the sailors blew the trumpets and alerted the soldiers of the fort, who fired the artillery, however without any effect on the French. The sailors abandoned the boats, of which three that were further away from land were captured by the French: a caravel, a war patache and another vessel.