Antiochus II Theos

Antiochus II also known by the nickname Antiochus Theos was the second son of Antiochus I and the third king of the Seleucid Empire.
Nickname.
After conquering Miletus and Ephesus and killing Timarchus of Miletus, Antiochus the Second gave himself the nickname Antiochus Theos meaning Antiochus the deity. 
Relationship with the Ptolemaic Empire.
Antiochus II went to war with Egypt but couldn’t win so he made peace with Ptolemy II Philadelphus by divorcing his wife Laodice I and instead marrying Ptolemy’s daughter Berenice Syra agreeing that his son by Berenice would be the next king of the Seleucid Empire. 
Death.
Berenice gave birth to a son who was also named Antiochus but then Antiochus II died and his first wife Laodice was accused of poisoning him. Berenice said her son Antiochus was the new king but Laodice said her son was King Seleucus II Callinicus and this led to a civil war.