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All Saints Day honors the saints in Heaven – those who have been recognized by the Church as saints, as well as those who have not been canonized. The feast was established in Rome as a result of the emperor’s giving of the Pantheon (the temple to all the gods) to the Church and its dedication to St. Mary and All the Martyrs. This followed the principle, "Christus vincit! Christus regnat! Christus imperat!” (Christ conquers, Christ reigns, Christ commands). Thus, throughout the Mediterranean many churches have been built over pagan sites, sanctifying them for Christ. The Church celebrates All Saints Day on November 1.