The War of Succession's main objective was to determine which European powers would dominate over the Atlantic trade. In 1713, the war ended with the Treaty of Utrecht which had significant impact on Spain's economic holdings. Spain lost some of its primary European possessions to the Austrian Habsburgs in addition to losing other territories such as the fortress of Sacramento, which brought the Portuguese in close proximity to Buenos Aires. In addition to its lost territory, Spain also had to grant a monopoly trade permit on the Atlantic slave trade, called an "asiento", to England. Granting this "asiento" not only led to a significant loss of revenue for the Spanish Crown, it also provided channels through which the English could deal in contraband trade. With these losses, Spain relied primarily on its American colonies to maintain its position as a European power.