Suppression of the Society of Jesus
Under the leadership of both the Jesuits and native caciques, the reductions achieved a high degree of autonomy within the Spanish colonial empire. With the use of native labour, the reductions became economically successful. When the incursions of Brazilian Bandeirante slave-traders threatened the existence of the reductions, Indian militias were set up which fought effectively against the Portuguese colonists. However, directly as a result of the Suppression of the Society of Jesus in several European countries, including Spain, in 1767, the Jesuits were expelled from the Guaraní missions (and the Americas) by order of the Spanish king, Charles III. So ended the era of the Paraguayan reductions. The reasons for the expulsion related more to politics in Europe than the activities of the Jesuit missions themselves.