In 1501 Castilian authorities delivered an ultimatum to Granada's Muslims: they could either convert to Christianity or be expelled. Most did convert, in order not to have their property and small children taken away from them. Many continued to dress in their traditional fashion, speak Arabic, and secretly practiced Islam (crypto-Muslims). The 1504 Oran fatwa provided scholarly religious dispensations and instructions about secretly practicing Islam while outwardly practicing Christianity. With the decline of Arabic culture, many used the "aljamiado" writing system, i.e., Castilian or Aragonese texts in Arabic writing with scattered Arabic expressions. In 1502, Queen Isabella I of Castile formally rescinded toleration of Islam for the entire Kingdom of Castile. In 1508, Castilian authorities banned traditional Granadan clothing. With the 1512 Spanish invasion of Navarre, the Muslims of Navarre were ordered to convert or leave by 1515.