the portuguese had maintained a presence in the area since explorers arrived in january of 1502 and, believing the bay to be the mouth of a river, christened the region rio de janeiro ('january river'). by mid-century they had yet to fully dominate the entirity of the brazilian coast, and their main points of strength remained in the northeast of the country.

meanwhile, the french elected to take advantage of the situation and establish their own colony in guanabara bay, 'antarctic france'.