Philadelphus had, when young, married Arsinoe the daughter of Lysimachus of Thrace, by whom he had three children—Ptolemy, who succeeded him, Lysimachus, and Berenice; but, having found that his wife was intriguing with Amyntas, and with his physician Chrysippus of Rhodes, he put these two to death, and banished the queen Arsinoe to Coptos in the Thebaid.
He then took Arsinoe his own sister as the partner of his throne. She had married first the old Lysimachus king of Thrace, and then Ceraunus her half-brother, when he was king of Macedonia. As they were not children of the same mother, this second marriage was neither illegal nor improper in Macedonia; but her third marriage, with Philadelphus, could only be justified by the laws of Egypt, their adopted country. They were both past the middle age, and whether Philadelphus looked upon her as his wife or not, at any rate they had no children. Her own children by Lysimachus had been put to death by Ceraunus, and she readily adopted those of her brother with all the kindness of a mother. This seeming marriage, however, between brother and sister did not escape blame with the Greeks of Alexandria. The poet Sotades, whose verses were as licentious as his life, wrote some coarse lines against the queen, for which he was forced to fly from Egypt, and being overtaken at sea he was wrapped up in lead and thrown overboard.
In the Egyptian inscriptions Ptolemy and Arsinoe are always called “the brother-gods”; on the coins they are called Adelphi, “the brothers”; and afterwards the king took the name of Philadelphus, or “sister-loving,” by which he is now usually known.
The wars between Philadelphus and his great neighbour Antiochus Theos seem not to have been carried on very actively, though they did not wholly cease till Philadelphus offered as a bribe his daughter Berenice, with a large sum of money under the name of a dower. Antiochus was already married to Laodice, whom he loved dearly, and by whom he had two children, Seleucus and Antiochus; but political ambition had deadened the feelings of his heart, and he agreed to declare this first marriage void and his two sons illegitimate, and that his children, if any should be born to him by Berenice, should inherit the throne of Babylon and the East. The peace between the two countries lasted as long as Philadelphus lived, and was strengthened by kindnesses which each did to the other.
Philadelphus was of a weak frame of body, and had delicate health; and though a lover of learning beyond other kings of his time, he also surpassed them in his unmeasured luxury and love of pleasure.
He reigned over Egypt, with the neighbouring parts of Arabia; also over Libya, Phœnicia, Cœle-Syria, part of Ethiopia, Pamphylia, Cilicia, Lycia, Caria, Cyprus, and the isles of the Cyclades. The island of Rhodes and many of the cities of Greece were bound to him by the ties of friendship, for past help and for the hope of future. The wealthy cities of Tyre and Sidon did homage to him, as before to his father, by putting his crowned head upon their coins. The forces of Egypt reached the very large number of two hundred thousand foot and twenty thousand horse, two thousand chariots, four hundred Ethiopian elephants, fifteen hundred ships of war, and one thousand transports. Of this large force, it is not likely that even one-fourth should have been Greeks; the rest must have been Egyptians and Syrians, with some Gauls.
These large forces were maintained by a yearly income, equally large, of fourteen thousand eight hundred talents, or two millions and a quarter pounds sterling, besides the tax on corn, which was taken in kind, of a million and a half of artabas, or about five millions of bushels. To this we may add a mass of gold, silver, and other valuable stores in the treasury, which were boastfully reckoned at the unheard-of sum of seven hundred and forty thousand talents, or above one hundred million pounds sterling.
The trade down the Nile was larger than it had ever been before; the coasting trade on the Mediterranean was new; the people were rich and happy; justice was administered to the Egyptians according to their own laws, and to the Greeks of Alexander, according to the Macedonian laws; the navy commanded the whole of the eastern half of the Mediterranean; the schools and library had risen to a great height upon the wise plans of Ptolemy Soter; in every point of view Alexandria was the chief city in the world. Athens had no poets or other writers during this century equal in merit to those who ennobled the Museum. Philadelphus, by joining to the greatness and good government of his father the costly splendour and pomp of an eastern monarch, so drew the eyes of after ages upon his reign that his name passed into a proverb.