In the title really. I was reading about the Empire during the reign of Domitian; as you know, his reign was marked by a few military ventures, notably the attempted conquest of Scotland under Julius Agricola. However Tacitus mentions (Tac. Ag. 24) that "Agricola, himself in the leading ship, crossed the Clota, and subdued in a series of victories tribes hitherto unknown".
Now this is my question; did the Romans perhaps send a brief expeditionary force to Ireland? If not, where is Tacitus referring to when he notes the brief foray into lands/tribes unknown?
We have lots of evidence for Roman presence i.e. coins along the Bru na Boinne area, and Tacitus mentioning it ("We know most of its/Hibernias harbours and approaches, and that through the intercourse of commerce"), but everything found suggests little in the nature of anything other than traders or visitors in a "non military context". Moreover, the rest of Tacitus Ag. 24 mentions that Agricola supposedly garrisoned troops along the coast in anticipation of a potential invasion, with an exiled Irish prince being the pretext (much in the same manner as the Claudian invasion of mainland Britain with Verica). Also he notes that Ireland could have been conquered with as little as 1 legion (and a few auxiliary cohorts). Therefore it seems to refute the candidacy of Ireland as the invaded lands mentioned in Ag. 24.
My initial thoughts are either the Isle of Man or perhaps the Isle of Arran, but with the lack of any real material evidence these are merely conjectural.
Any thoughts lads?