Vespasia was the mother of the Roman emperor Vespasian; he was definitely one of the better emperors, an honest and diligent politician and a good soldier. Definitely a pagan! He completed the pacification of Judaea (i.e. put down the rebellion of the Jews), not for religious reasons but simply as a political action. His modesty and sense of humour have always appealed to me, assuming of course that he wasn't being serious: Roman emperors were regularly deified after their death, and his dying words were: Puto deus fio (I think I'm becoming a god).
Which is another way of saying that the putative link with vespers does not exist!