During the fight against the Spanish and the Portuguese, privateering was legal. This has been the main goal and source of income for the Dutch West India Company since their establishment in 1621. Between 1623 and 1636, 547 Spanish and Portuguese ships were hijacked. After this, the Groot Desseyn was developed, the big plan. By taking over the slave trade the Portuguese sugar cane trade from Brazil could be undermined. With the capture of a Spanish treasure fleet during the Battle in the Bay of Matanzas in 1628, sufficient money was available to carry out the Groot Desseyn. Between 1630 and 1634 Recife and a large part of the Brazilian coast was conquered, this became Dutch Brazil. In 1637, Fort St. George in Elmina on the African Gold Coast (in the Gulf of Benin) was captured. this was till then the greatest Portuguese slave trade stronghold. In the centuries that followed, this fortress would become one of the centres of the WIC's slave trade. In 1641 Luanda (located in what is now Angola) was conquered from the Portuguese. Around 1700, the WIC owned a dozen trading fortresses on the West African coast.