Seoán Ó Leaáin

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Seoán Ó Leaáin, Bishop of Clonfert, 1322–1336. Ó Leaáin appears to have been a member of the same family as

Mauricius Ó Leaáin (Bishop of Kilmacduagh 1254–1284), Nicol Ó Leaáin, (ditto, 1358–1393) and Gregorius Ó Leaáin (1394–1397).

Previously Archdeacon of Tuam. He was elected 10 November 1319, but wasn't appointed until 6 August 1322. Ó Leaáin was consecrated 20 September and received possession of temporalities 29 December 1322. After his death on 7 April 1336, the see lay vacant for as many as ten years. However, at some point prior to 14 October 1437, he was succeeded by a prince of the Ui Maine dynasty, Tomás mac Gilbert Ó Cellaigh.