Da Gama in 1498 marked the beginning of Portuguese influence in Indian Ocean. In 1503 or 1504, Zanzibar became part of the Portuguese Empire when Captain Ruy Lourenço Ravasco Marques landed and demanded and received tribute from the sultan in exchange for peace. Zanzibar remained a possession of Portugal for almost two centuries. It initially became part of the Portuguese province of Arabia and Ethiopia and was administered by a governor general. Around 1571, Zanzibar became part of the western division of the Portuguese empire and was administered from Mozambique. It appears, however, that the Portuguese did not closely administer Zanzibar. The first English ship to visit Unguja, the "Edward Bonaventure" in 1591, found that there was no Portuguese fort or garrison. The extent of their occupation was a trade depot where produce was purchased and collected for shipment to Mozambique. "In other respects, the affairs of the island were managed by the local 'king,' the predecessor of the Mwinyi Mkuu of Dunga." This hands-off approach ended when Portugal established a fort on Pemba around 1635 in response to the Sultan of Mombasa's slaughter of Portuguese residents several years earlier.