This bishopric was established early in the sixth century, and was considerably the largest in Ireland, extending over a great part of the counties of Galway and Mayo, and including a part of Roscommon.
It was upwards of sixty miles long, and fifty broad.
With this see the bishopric of Ardagh had been held in commendam by the Archbishop.
THE PALACE, Tuam, was built between 1716 and 1741 by the Most Rev Edward Synge, Lord Archbishop of Tuam between those dates.
It is thought that a further six archbishops resided at the palace, the last prelate being the Most Rev Power le Poer Trench, Lord Archbishop of Tuam and Primate of Connaught, 1819-39.
Thereafter the archbishopric merged with the diocese of Killala and Achonry.
The palace was remodelled by 1823.
This is a three-storey, seven-bay house over a basement, with a full length three-bay breakfront.
The walls are rendered.
Its large scale and formal design, with good limestone detailing, is said to be typical of important religious residences.
It stands prominently in Bishop Street, opposite the precinct of the Roman Catholic cathedral.
The palace was vacated in the early 1950s and was for a time used as sleeping quarters for the boarders at Presentation College, Currylea, until the boarders were phased out in the early 1990s.
It was then taken over by a local supermarket owner, restored; and now has a restaurant on the ground floor known as The Palace Restaurant.