Ptolemy IX (Ptolemy Soter II) was king of Egypt three times, from 116 BC to 110 BC, 109 BC to 107 BC and 88 BC to 80 BC, with intervening periods ruled by his brother, Ptolemy X Alexander.

At first he was chosen by his mother Cleopatra III to be her co-regent (his father Ptolemy VIII wished that she would rule with one of her sons), though she was more forced to choose him by the Alexandrians. He married his sister Cleopatra IV, but his mother pushed her out and replaced her with his younger sister Cleopatra Selene. Later, she claimed that he tried to kill her, and successfully deposed him, putting her favorite son Alexander on the throne as co-regent with her. However, she later grew tired of the now Ptolemy X and deposed him, putting Ptolemy IX back on the throne. She was soon murdered by Ptolemy X, who took the throne again. He was then killed in battle, and Ptolemy IX reigned until his own death.

His daughter Berenice III took the throne after his death, and reigned for about a year. She was forced to marry her stepson Alexander, who reigned under the name Ptolemy XI and had her killed 19 days later.

Ptolemy IX's name recalls that of his great ancestor, Ptolemy I Soter; note that in older references, he may be numbered VIII.

Comments

Numbering the Ptolemies is a modern invention; the Greeks distinguished them by nickname. The number given here is the present consensus; but there has been some disagreement about which Ptolemies should be counted as reigning. Older sources may give a number one higher or lower, but the same epithet.

Preceded by: Ptolemy VIII	Ptolemaic King of Egypt First Reign with Cleopatra III and Cleopatra IV	Succeeded by: Ptolemy X and Cleopatra III
Ptolemy X and Cleopatra III	Ptolemaic King of Egypt Second Reign	Ptolemy X
Ptolemy X	Ptolemaic King of Egypt Third Reign	Berenice III