On 31 March 1492 the Catholic Monarchs, Ferdinand and Isabella, issued the Alhambra Decree, also known as the Edict of Expulsion, giving notice to all practising Jews to leave the kingdoms of Castile and Aragón and their territories and possessions by the end of July in the same year.
They were permitted to take all their belongings (except gold, silver and minted money) with them, and were promised safe passage during that three-month period. If they failed to comply and leave by the deadline, however, they would face execution.
During the seven centuries of Moorish rule in Spain the Jews had held a privileged position in society and coexisted happily alongside their Muslim rulers. When Ferdinand and Isabella set about reconquering Spain, however, they wanted to ensure that it became a truly Christian country and as a result many Jews suffered violent hostility and repression. Many decided to convert to Christianity, at least for appearances' sake. The king and queen became concerned that practising Jews would influence these 'conversos', many of whom were unconvincing Catholics anyway, persuade them to take up Judaism once more and would also "try to draw faithful Christians away from their beliefs."
About half of all Jews had converted by this time. As a result of this decree over 200,000 others did the same and many (some historians claim that the figure is as high as 100,000) left the country. A large number are thought to have secretly returned in the following years.
Remarkable though it may seem, the Alhambra Decree was not formally revoked until 16 December 1968; by that time the Laws of Religious Freedom had been in force for 100 years, meaning that Jews had been able to openly practise their religion in Spain again, and use synagogues as places of worship.
As an effort to compensate Jewish people for their suffering in the past, in 2014 the Spanish government approved a law which enables their descendants to hold dual nationality.
This means that Sephardic Jews who can prove that their forefathers were expelled from the country by the Christian Monarchs under the Alhambra Decree are now able to hold Spanish nationality without having to live in Spain or give up their existing nationality.