The Portuguese had been troubled by the presence of French ships on the coast throughout the first half of the sixteenth century. The competition for dyewood lay at the heart of the rivalry, and both the French and the Portuguese mobilized indigenous allies to attack their rivals. In 1555, the French established an outpost at Fort Coligny on an island in Guanabara Bay. Although the colony established good relations with the local indigenous population, eventually squabbling between its Huegenot and Catholic members and the authoritarian rule of its leader, Nicholas Durand de Villegagnon, weakened the colony. The Portuguese destroyed the colony in 1560 and established their own settlement, São Sebastião do Rio de Janeiro on the shores of Guanabara Bay, in 1563. In the following letter, the seriousness of the French threat is made clear.

(From História da Colonização Portuguesa do Brasil, vol. III, p. 377.)