(Πτολεμαῖος king of EGYPT, surnamed ALEXANDER, whence he is generally distinguished as ALEXANDER I., was the youngest son of Ptolemy VII. by his niece Cleopatra. His mother's partiality led her to desire to place him on the throne in conjunction with herself, on the death of Euergetes, B. C. 1 7, in preference to his elder brother. But the will of the Alexandrians having compelled her to assume Lathyrus as her colleague, she sent Alexander to Cyprus with the title of general or governor of that island. Three years later, however (B. C. 114), he assumed the title of king, on what pretext we know not, and reckoned the years of his reign from this date (Porphyr. apud euseb. Arm. p. 116). But he appears to have remained content with the possession of Cyprus till B. C. 107, when Cleopatra, having expelled Ptolemy Lathyrus, recalled her favourite son to occupy the vacant throne of Egypt. Alexander reigned conjointly with his mother from this time till B. C. 90: but it is probable that her haughty and imperious character left him little real part in the administration of affairs. The only occasion on which we meet with his name in this interval is in B. C. 102, when he commanded the Egyptian fleet which attacked Phoenicia by sea, while Cleopatra with the army marched against Palestine (J. AJ 13.13.1). But at length the violence and cruelties of his mother terrified Alexander to such a degree that He determined to free himself from her power, and made his escape secretly from Alexandria. Hereupon Cleopatra, fearing lest her sons should make common cause against her, sent an embassy to Alexander to entreat his return. With this request he was induced to comply; but soon found reason to suspect that she was forming designs against his life, and immediately determined to anticipate them by causing her to be assassinated, B. C. 90. But he did not long enjoy the fruits of this crime. Cleopatra had been popular with the army, and the soldiers in consequence hated Alexander, who had not reigned alone a year, when he was compelled by a general sedition of the populace and military to quit Alexandria. He however raised fresh troops, and attempted to overcome the insurgent soldiery, but was totally defeated in a sea-fight by the rebels under Tyrrhus, and fled for refuge to Myra in Lycia, B. C. 89. His brother Lathyrus was now recalled by the Alexandrians to Egypt, a circumstance which led Alexander to hope that he might make himself master of Cyprus, and he accordingly assembled some forces, and invaded that island, but was defeated in a naval action by Chaereas, and fell in the battle. (Just. 39.4, 5; Porphyr. apud Euseb. Arm. p. 116.)
He left two children: a son, Alexander, who afterwards ascended the throne of Egypt, and a daughter, of whom nothing more is known. (Porphyr. l.c.)
[E.H.B]