HIBERNIA, in ancient geography, one of the names by which Ireland was known to Greek and Roman writers. Other names were lerne, Iuverna, Iberio. All these are adaptations of a stem from which also Erin is descended. The island was well known to the Romans through the reports of traders, so far at least as its coasts. But it never became part of the Roman empire. Agricola (about A.D. 8o) planned its conquest, which he judged an easy task, but the Roman government vetoed the enterprise. During the Roman occupation of Britain, Irish pirates seem to have been an intermittent nuisance, and Irish emigrants may have settled occasionally in Wales; the best attested emigration is that of the Scots into Caledonia. It was only in post-Roman days that Roman civilization, brought perhaps by Christian missionaries like Patrick, entered the island.