Ineresting view....I have always thought this
Many scholars see another historical allusion in Mk 5:8-13 to a 'Legion' which had a pig as its emblem and which Josephus tells us remained in Jerusalem in the war's aftermath (Wars of the Jews 7.1.3). William Harwood writes in Mythology's Last Gods: "Since the fall of the city a few months earlier [in 70 C.E.], Jerusalem had been occupied by the Roman Tenth Legion [X Fretensis], whose emblem was a pig. Mark's reference to about two thousand pigs, the size of the occupying Legion, combined with his blatant designation of the evil beings as Legion, left no doubt in Jewish minds that the pigs in the fable represented the army of occupation. Mark's fable in effect promised that the messiah, when he returned, would drive the Romans into the sea as he had earlier driven their four-legged surrogates."