Ó Longáin, Mícheál Óg (Michael Long) (1766–1837), scribe, poet, and schoolteacher, was born 1 August 1766 in Carrignavar, Co. Cork, the son of Mícheál mac Peattair Ó Longáin (qv), also a scribe. His father died when he was four and his mother when he was eight. He then went to live with Father Dónall Ó Cearúill for two years in West Carbery, after which he returned home, attended school for a time, and then worked as a cowherd. At eighteen he went back to school for another two years.
Having taught himself the craft of the scribe, Ó Longáin began transcribing manuscripts in the years 1785–6 in the houses of various people in his home parish. He moved frequently over the years, earning a meagre living from teaching and occasional labour, but rarely straying far from his own locality, apart from five years that he spent in north-east Kerry and west Limerick (1802–7). In 1800 he married Máire Ní Leidhin, a widow who had one daughter. The years 1817–20 were among his most productive, when he lived in Cork city and enjoyed the patronage of, among others, Dr John Murphy (qv), catholic bishop of Cork. From 1822 onwards he lived and worked at Knockboy in Carrignavar parish, where one of his sons had acquired an 11-acre farm. He was one of the most prolific scribes of the later period of the manuscript tradition and wrote, or part-wrote, more than 150 extant manuscripts containing material from all periods of Irish literature.
A member of the Whiteboys in his youth, he was active in the United Irishmen during 1797–8 and was on the run from the authorities in 1799. As a poet, he is noteworthy for turning away from the Jacobite tradition of poetry in Munster and espousing republicanism. He wrote more than 350 poems and is best remembered for ‘Maidin Luan Chincíse’ and ‘Buachaillí Loch Garman’, both of which castigate Munster for not supporting the 1798 rebellion. An edition of his poetry, Mícheál Óg Ó Longáin, file (1994), was edited and published by Rónán Ó Donnchadha, although there are still many of his poems that have never been published.
With his wife he had five sons and two daughters; three of their sons, Peadar, Pól, and Seosamh, became scribes in their own right. Ó Longáin died at his home in Knockboy on 17 May 1837 and was buried at Whitechurch, Co. Cork. Many of his manuscripts are held in the RIA and there is a comprehensive listing of his manuscripts in Ó Conchúir.