@ned One interpretation, if we're reading only from Daniel, is that it's Antiochus IV Epiphanes. A ruler who set up an altar to Zeus in the Temple and sacrificed a pig.

However, since Jesus quotes the prophecy from Daniel it could refer to the then coming destruction of Jerusalem and the Temple or it could be referring to the Antichrist. Antiochus himself could still be a partial fulfillment with him prefiguring the coming Antichrist.