1911 Encyclopædia Britannica/Alexander Balas
ALEXANDER BALAS (i.e. "lord"), ruler of the Greek kingdom of Syria 150-146 B.C., was a native of Smyrna of humble origin, but gave himself out to be the son of Antiochus IV. Epiphanes and heir to the Syrian throne. His claims were recognized by the Roman senate, Ptolemy Philometor of Egypt and others. At first unsuccessful, he finally defeated the reigning king Demetrius Soter in 150 B.C. Being now undisputed master of Syria, he abandoned himself to a life of debauchery. Demetrius Soter's son profited by the opportunity to regain the throne. Ptolemy Philometor , who was Alexander's father-in-law, went over to his side, and Alexander was defeated in a pitched battle near Antioch in Syria. He fled for refuge to a Nabataean prince, who murdered him and sent his head to Ptolemy, who had been mortally wounded in the engagement.
See 1 Maccab. 10 ff.; Justin xxxv. 1 and 2; Josephus, Antiq. xiii. 2.; Appian, Syr. 67; Polybius xxxiii. 14.