Serapis was a Greco-Egyptian deity who was created by the Macedonian Ptolemaic ruler Ptolemy I Soter in 323 BC as a syncretism of the Greek deities Hades and Demeter and the Egyptian deities Osiris and Apis. Ptolemy created the cult as a means of fusing Hellenism and Kemetism, as he hoped to create unity between the new Greco-Macedonian elite of Ptolemaic society and the native Egyptian majority population. During the reign of Ptolemy III Euergetes, a temple to Serapis - the Serapeum - was built in Alexandria. In 389 AD, a Christian mob destroyed the Serapeum, and Serapis' cult survived until Theodosius I suppressed the religion in 391 AD.