The name "Ammiraglio" ("admiral") derives from the founder of the church, the Syrian christian admiral and principal minister of King Roger II of Sicily, George of Antioch. The foundation charter of the church (which was initially Eastern Orthodox), in ancient Greek and Arabic, is preserved and dates to 1143; construction may already have begun at this point. The church had certainly been completed by the death of George in 1151, and he and his wife were interred in the narthex. In 1184 the Arab traveller Ibn Jubayr visited the church, and later devoted a significant portion of his description of Palermo to its praise, describing it as "the most beautiful monument in the world." After the Sicilian Vespers of 1282 the island's nobility gathered in the church for a meeting that resulted in the Sicilian crown being offered to Peter III of Aragon.