Antiochus III and Seleucis IV, the rulers of the Seleucid Empire before Antiochus IV, were rather nice to the Jews. They let them do their religion, even though they didn't worship them because the Jews refuse to worship anyone or anything other than Hashem.
The Seleucid Empire was part of the Persian Empire of Alexander the Great which was split up after his death. The other parts were the Mauryan Empire, the Parthian Empire, and the Sasanid Empire.