<P> In Roman mythology, Mezentius was an Etruscan king, and father of Lausus . Sent into exile because of his cruelty, he moved to Latium . He reveled in bloodshed and was overwhelmingly savage on the battlefield, but more significantly to a Roman audience he was a contemptor divum, a "despiser of the gods ." </P> <P> He appears in Virgil's Aeneid, primarily book ten, where he aids Turnus in a war against Aeneas and the Trojans . While in battle with Aeneas, he is critically injured by a spear blow, but his son Lausus bravely blocks Aeneas's final blow . Lausus is then killed by Aeneas, and Mezentius is able to escape death for a short while . Once he hears of Lausus' death, he feels ashamed that his son died in his place and returns to battle on his horse Rhaebus in order to avenge him . He is able to keep Aeneas on the defensive for some time by riding around Aeneas and loosing javelins . Eventually, Aeneas kills the horse with a spear and pins Mezentius underneath . He is overcome by Aeneas, but remains defiant and fearless unto his death, not begging for mercy as Turnus later does, but simply asking that he be buried with his son . </P>

Under what circumstance did mezentius come to join the rutulians