St. Oliver Plunkett lived at Ballybarrack on the outskirts of Dundalk for a substantial period of time in the 1670s and he ordained many priests in the area including Castletown and Dundalk.

Ballybarrack church measures fifteen metres by five metres, but may well have been smaller than this as it is believed that St. Oliver's home was probably situated towards the front of the church alongside the road. At the time of its excavation in the early twentieth century, the top of a sixteenth century thurible was found with a Celtic motif, which is now in Maynooth College Museum. Perhaps someone fleeing from capture dropped it in haste.

After being arrested in 1679, he spent some time in jail in Dundalk but was not found guilty of the charges against him at Dundalk. Subsequently Archbishop Oliver Plunkett was taken to London where he was found guilty as a result of trumped-up charges and he was martyred in Tyburn in 1681. St. Peter's Church in Drogheda is world-famous for the relics of Saint Oliver Plunkett, which are housed there in a special shrine on the altar.

Ballybarrack and also Ardpatrick, located on a hill overlooking Louth village, have both been described as St. Oliver's pro-cathedrals. Without pillars or spires these tiny churches in rural areas had been overlooked and obviously considered of little value to those who had commandeered almost everything else. However, they were destined to serve St. Oliver's humble mission to his flock throughout the 1670's.

He lived in both locations, ordained many priests in both small churches and held an important Ulster Church Synod at Ardpatrick in 1678.

We know that his homes were not lofty palaces but simple, humble abodes and he wrote on one occasion that his home was a thatched abode with a low ceiling of only seven feet high. That did not confine him however in his hospitality to friends, strangers or visiting priests. In a rural area, safe from prying eyes, there must have been a lot of coming and going at these locations in north Co. Louth.