Bandeirantes

Sao Paulo's history only makes sense once you realize it's role in the inevitable gold rush that was precipitated by bandeirantes... What are bandeirantes?

From v-Brazil.com, which has more:
Bandeirantes were the organizers of bandeiras (bandeira is the Portuguese for "flag"; the bandeiras used to carry a flag to identify them), private expeditions which explored the interior lands of Brazil during the century 17 and in the early years of century 18.

Portugal had a limited interested in exploring the vast lands of Brazil; for decades after the discovering, all that Portugual did was to establish some trading points along the coast, barely enough to store the goods (mostly wood, minerals and stones) which would be sent to the metropolis. Besides, Portugal was restrained by the Treaty of Tordesillas, which determined the boundaries between Portuguese and Spanish domains; the bandeirantes had no limits to respect.

The bandeirantes were, above all, greedy men. They wanted the wealthiness that the Portuguese didn't bother to explore. Their goal was not to conquer land (as it was happening in the US), but to find gold, stones, and to imprison indians which would be sold as slaves.

A typical bandeira would consist of 2-3 hundred men, who would stay for months or years exploring the wild forests and fields. Each bandeira had to be organized and paid for by someone who had to be rich and bold; on return, these men would become richer and more respected by the community.