(Δημήτριος) III., king of SYRIA, surnamed EUCAERUS, was the fourth son
of Antiochus Grypus, and grandson of Demetrius II. During the civil wars that followed the
death of Antiochus Grypus, Demetrius was set up as king of Damascus or Coele Syria, by the aid
of Ptolemy Lathurus, king of Cyprus; and after the death of Antiochus Eusebes, he and his
brother Philip for a time held the whole of Syria. (J. AJ
13.13.4.) His assistance was invoked by the Jews against the tyranny of Alexander
Jannaeus; but though he defeated that prince in a pitched battle, he did not follow up his
victory, but withdrew to Beroea. War immediately broke out between him and his brother Philip,
and Straton, the governor of Beroea, who supported Philip, having obtained assistance from the
Arabians and Parthians, blockaded Demetrius in his camp, until he was compelled by famine to
surrender at discretion. He was sent as a prisoner to Mithridates, king of Parthia (Arsaces
IX.), who detained him in an honourable captivity till his death. (J. AJ
13.14.) The coins of this prince are important as fixing the chronology of his reign;
they bear dates from the year 218 to 224 of the era of the Seleucidae, i.
e.B. C. 94-88. The surname Eucaerus is not
found on these coins, some of which bear the titles Theos Philopator and Soter; others again
Philometor Euergetes Callinicus. (Eckhel, iii. pp. 245-6.)