St Patrick's Confession, in Latin, written by him is the earliest Irish historical document. It gives some information about the Saint.[17] On the other hand, according to Prosper of Aquitaine, a contemporary chronicler, Palladius was sent to Ireland by the Pope in 431 as "first Bishop to the Irish believing in Christ", which demonstrates that there were already Christians living in Ireland. Palladius seems to have worked purely as Bishop to Irish Christians in the Leinster and Meath kingdoms, while Patrick – who may have arrived as late as 461 – worked first and foremost as a missionary to the pagan Irish, in the more remote kingdoms in Ulster and Connacht.