Thaddeus MacCarthy, of Munster, Ireland, became bishop of Ross at the age of twenty-seven, exhibiting great zeal for the salvation of souls and a deep dedication to preaching. But despite the fact that Bishop MacCarthy had been appointed by Pope Sixtus IV, an auxiliary bishop of Ross claimed the episcopal seat for himself. An earl supporting this rival claimant even confiscated church property from Bishop MacCarthy, forcing him out of his own see. In the end, Pope Sixtus’ successor Innocent VIII reassigned Bishop MacCarthy to the conjoined Irish sees of Cork and Cloyne. But when the bishop came to take possession of his new episcopal charge, he found himself barred from his cathedral by laymen opposed to his rule. Journeying to Rome to plead his cause, Bishop MacCarthy obtained Pope Alexander VI’s full support. As Bishop MacCarthy was traveling back from Rome, humbly disguised as a pilgrim, he died quite suddenly while lodged at Ivrea, Italy. Many miracles occurred at his tomb.
He was beatified in Rome in 1896. Following his beatification, a relic of his remains was sent by the people of Ivrea to the Cathedral in Cork. The reliquary was remounted on a piece of carved Cork limestone by Ken Thompson as part of the 1996 refurbishment of the Cathedral of St. Mary and St. Anne.