The foundation of Macapá was a key moment in the colonial history of Brazil, initiated by the Portuguese explorer Sebastião Veiga Cabral. Located at the mouth of the Amazon River, Macapá was strategically positioned to serve as a colonial outpost that would enhance Portugal's influence in the region. Cabral, serving under the auspices of the Portuguese crown, recognized the importance of this location for maritime navigation and commerce flowing into and out of the vast Amazon basin.

Cabral's expedition was also aimed at consolidating power amidst conflicts with other colonial powers and indigenous populations. By establishing a permanent settlement, Cabral sought not only to secure the territory against rival claims but also to promote the Portuguese agenda of expansion in South America. The name 'Macapá' is derived from the indigenous language, reflecting the integration of local cultures into Portuguese colonial existence.

The early years of Macapá were characterized by interactions between the Portuguese settlers and local indigenous tribes. This blending of cultures led to a unique societal framework that contributed to the city’s identity. Moreover, Macapá's position as a key gateway to the interior Amazon made it a pivotal point for trade and military expeditions in the decades that followed, solidifying its status in colonial administration.