Antiochus III was the father of the infamous Antiochus IV Epiphanes of I and II Maccabees fame who desecrated the Jewish temple (prophesied by the prophet Daniel) ...Yet some still deny Maccabees their place in the canon of Scripture. (No room for have any of that prayers-for-the-dead stuff, dontcha know ...)
Even if they don’t accept Maccabees as inspired, at least it confirms the fact that Catholics did not “invent” prayers for the dead an Purgatory (praying for the dead makes no sense if there is only heaven and hell). The Jews, God’s people, were doing it long before Catholics. They do to this day.