by loss of prestige, the Empire became vulnerable to rebels in the eastern areas of the empire, who began to further undermine the empire while the Parthians moved into the power vacuum to take over the old Persian lands. Antiochus' aggressive Hellenizing (or de-Judaizing) activities provoked a full scale armed rebellion in Judea—the Maccabean Revolt. Efforts to deal with both the Parthians and the Jews as well as retain control of the provinces at the same time proved beyond the weakened empire's power. Antiochus orchestrated a military campaign, capturing Artaxias I, King of Armenia, and reoccupying Armenia. His offensive ventured as far as Persepolis, but he was forced from the city by the populace. On his return home, Antiochus died in Isfahan in 164 BC. Civil war and further decay After the death of Antiochus IV Epiphanes, the Seleucid Empire became increasingly unstable. Frequent civil wars made central authority tenuous at best. Epiphanes' young son, Antiochus V Eupator, was first overthrown by Seleucus IV's son, Demetrius I Soter in 161 BC. Demetrius I attempted to restore Seleucid power in Judea particularly, but was overthrown in 150 BC by Alexander Balas – an impostor who (with Egyptian backing) claimed to be the son of Epiphanes. Alexander Balas reigned until 145 BC when he was overthrown by Demetrius I's son, Demetrius II Nicator. Demetrius II proved unable to control the whole of the kingdom, however. While he ruled Babylonia and eastern Syria from Damascus, the remnants of Balas' supporters – first supporting Balas' son Antiochus VI, then the usurping general Diodotus Tryphon – held out in Antioch. Meanwhile, the decay of the Empire's territorial possessions continued apace. By 143 BC, the Jews in the form of the Maccabees had fully established their independence. Parthian expansion continued as well. In 139 BC, Demetrius II was defeated in battle by the Parthians and was captured. By this time, the entire Iranian Plateau had been lost to Parthian control. Demetrius Nicator's brother, Antiochus VII Sidetes, took the throne after his brother's capture. He faced the enormous task of restoring a rapidly crumbling empire, one facing threats on multiple fronts. Hard-won control of Coele-Syria was threatened by the Jewish Maccabee rebels. Once-vassal dynasties in Armenia, Cappadocia, and Pontus were threatening Syria and northern Mesopotamia; the nomadic Parthians, brilliantly led by Mithridates I of Parthia, had overrun upland Media (home of the famed Nisean horse herd); and