With the caliphate based in Cairo, Muslim rulers from all over the Islamic world looked to Egypt for legitimisation of their reign. Throughout the empire, energetic Mamluk sultans like Baybars I, Qalawun, Nasr al-Din Muhammad ibn Qalawun, Hassan and Qaytbay, initiated the building of splendid mosques and religious institutions, and commissioned magnificent Qur’an manuscripts and mosque furnishings to grace their interiors.