Antiochus IV Epiphanes (originally named Mithradates, but renamed Antiochus either upon his ascension or after the death of his elder brother Antiochus) (175 - 163 BC) was one of the Seleucid emperors, son of Antiochus III the Great and brother of Seleucus IV Philopator. Antiochus rose to power after the death of the latter; he had been hostage in Rome following the peace of Apamea in 188 BC but had lately been exchanged for the son and rightful heir of Seleucus IV, the laterDemetrius I Soter. Taking advantage of this situation, Antiochus could easily proclaim himself as co-regent with another of Seleucus' sons, the infant Antiochus, whom he had murdered a few years later.
Notable events during his reign include the near-conquest of Egypt, which was halted by the threat of Roman intervention, and the beginning of the Jewish revolt of the Maccabees. He was succeeded by his infant son, Antiochus V Eupator.
In a spirit of revenge he organized an expedition against Jerusalem, which he destroyed, as well as putting vast multitudes of its inhabitants to death in the most cruel manner. From this time the Jews began the war of independence under their heroic Maccabean leaders with marked success, defeating the armies of Antiochus that were sent against them. Enraged at this, Antiochus is said to have marched against them in person, threatening utterly to exterminate the nation; but on the way he was suddenly arrested by the hand of death (164 BC). The exact causes of the Jewish revolt, and of Antiochus' response to it, are uncertain. His last years were spent on a campaign against the rising Parthian empire, which seems to have been initially successful but was terminated with his death.
The reign of Antiochus was a last period of strength for the empire, but in some way it was fatal; being an usurper and leaving no successor except a little boy, his death was followed by devastating dynastic wars.
The above paragraph is modified from Easton's Bible Dictionary
Seleucus IV Philopator
Antiochus V Eupator
Seleucus IV Philopator
Mithridates of Parthia
(By the end of Antiochus IV's reign, the rule of Persia had passed firmly to the kings of Parthia. Articles for the Parthian kings have not yet been completed. Please feel free to skip ahead to Ardashir I of Persia, the first ruler of the Sassanid dynasty, to continue following the line of Persian kings.)