On 5 December 1496, King Manuel I of Portugal decreed that all Jews must convert to Catholicism or leave the country, in order to satisfy a request by the Catholic Monarchs of Spain during the negotiations of the contract of marriage between himself and their eldest daughter Isabella, Princess of Asturias, as an unstated condition to win her hand. The King demonstrated his wish to completely and forever eradicate Judaism from Portugal by issuing two decrees. The initial edict of expulsion of 1496 was turned into an edict of forced conversion in 1497, whereby Portuguese Jews were prevented from leaving the country and were forcibly baptized and converted to Christianity. Those Jews who refused to pay taxes in protest were deported from Portugal and abandoned to their fate in the islands of São Tomé and Príncipe, off the western coast of Africa. Hard times followed for the Portuguese "conversos", with the massacre of 2,000 people in Lisbon in 1506, and later the establishment of the Portuguese Inquisition in 1536.