The tombstone was created 66 years after the Norman conquest of Arabic Palermo. Norman Sicily would grow to become a regional powerhouse and a cultural melting pot. The tombstone was created to commemorate the death of Anna, the mother of a noble priest named Grisanto. These types of headstones are common from the Norman period.
Interestingly, in the Arabic text, the Cathedral of Palermo, formerly the Great Mosque of the city, is referred to as a جامع, while the Pope is referred to as the 'imam of Rome'. It underscores that the intended audience was one drawn from different religions.
by Bnedem