Mamlūk Egypt witnessed a great degree of pressure on non-Muslims, and saw the conversion of many to Islam. In 1301, riots led to the closure of numerous houses of worship of non-Muslims, an act supported by a fatwā written by Najm al-Dīn ibn al-Rifā. Ibn al-Rifā offered five arguments against maintaining dhimmī houses of worship: (1) non-Muslims seeking to preserve their houses of worship must always be considered plaintiffs, that is, that the burden of proof falls upon them; (2) The contradiction between arguments that there were no synagogues or churches prior to the building of the city and those arguing for preservation based on maintaining existing buildings must be resolved by placing the burden of proof on the dhimmīs; (3) There was no peace agreement in Cairo, a necessary precondition for allowing non-Muslims to retain their houses of worship; (4) Even were there a peace agreement, it would have lapsed; and (5) Dhimmīs must prove they have not contravened individual terms of the treaty, even unrelated to houses of worship. Ibn al-Rifā's fatwā generated much support, but eventually the churches and synagogues were returned to their communities. Nevertheless, it reflects the attitudes of the times and was part of the pressures which led to greater conversion to Islam.