In 1924 W. W. Tarn published an article in which he attempted to prove that the mother of Philip V of Macedon was the Epirot princess Phthia. Previously all historians had accepted the statement of Eusebius that Philip was the son of Demetrius II and Chryseis, whom, after the death of her husband, the Macedonians gave in marriage to Antigonus Doson. Despite the cogency of Tarn's arguments, his theory has been rejected by both Beloch and Dinsmoor, who adhere to the (...) traditional view. This problem of the identity of Philip's mother is one of considerable importance, and consequently in this paper I intend to collect the evidence once again and subject it to a careful analysis. The results will be found strongly to corroborate Tarn's contention. (shrink)