Ptolemy VI Philometor

Ptolemy VI became king in 180 BC when his father died, ruling under regents until 169 BC - first his mother Cleopatra I, then two of her associates. From 170 BC he shared power with his sister-wife Cleopatra II and younger brother Ptolemy VIII, a arrangement that bred conflict for decades. The Sixth Syrian War brought utter defeat: Seleucid armies invaded Egypt twice between 170 and 168 BC. In 164 BC his brother expelled him from the country entirely. Alexandria's people turned against Ptolemy VIII the next year and invited Ptolemy VI back, and this second reign proved sharper. He banished his brother to Cyrenaica, blocked repeated attempts to seize Cyprus despite Roman backing for Ptolemy VIII, and fueled a Seleucid civil war by backing rival claimants to their throne. In 145 BC he invaded Syria and won total victory at the Battle of the Oenoparus, seizing control of both realms - then died from his battle injuries three days later. Ptolemy VIII retook Egypt; the gains vanished.