The real birth of Brazil can be traced to the remote Jesuit village of São Paulo de Piratininga, founded in 1554, after arduous efforts to ascend the Serra do Mar. This isolated settlement, inhabited by a mixture of Indigenous peoples and Portuguese colonizers, became the pivotal point for the expansion of Portuguese territory in South America. The people of São Paulo, or paulistas, shaped by their harsh environment and violent history, forged a unique identity. Through their relentless expeditions, the bandeirantes ventured deep into the interior, hunting Indigenous peoples for slavery and expanding the Portuguese domain beyond the boundaries defined by European treaties. This essay explores how the humble origins of São Paulo de Piratininga grew into a force that shaped the modern Brazilian state and its borders.