Ó hUaithnín, Seon (b. c.1688), poet, was born in Kilshanny, north of Ennistymon, Co. Clare, eldest son of Walter Huonyn (the name took many anglicised forms) of Tullamore in the parish of Killaspuglonane; nothing is known of his mother. Little is known of him, apart from some scant manuscript accounts and seventeen poems which have survived. He was a popular figure, ‘one of the most athletick men of his time’ (MS SF 2.14, Russell Library, Maynooth), and had earned the reputation of a rake. He was, however, the intimate of some of the better known poets of Clare in the early eighteenth century, such as Aodh Buí Mac Cruitín (qv) and Micheál Coimín (Michael Comyn (qv)). It was the latter who in court in Ennis modified in translation a seditious Jacobite poem of Ó hUaithnín and obtained his acquittal from a charge of high treason. Ó hUaithnín is reputed to have cried out in Irish in the court ‘O Michael, though I be hanged for it, do not spoil the song!’ It was soon after this that he left Ireland, evidently quite young, as Spanish military records give his age as 33 in 1721. His father, who forbade him to compose any more such poems, was a man of some standing and was high constable of the barony of Corcomroe in 1701. In 1704, under the registration act of that year, he stood surety of £50 each for two registered catholic priests. His name is among the subscribers to Aodh Buí Mac Cruitín's A brief discourse in vindication of the antiquity of Ireland (1717). Seon Ó hUaithnín's younger brother, Daniel, had already left Ireland. He served in the British navy but later transferred to the Spanish navy, where he reached the rank of admiral.
Ó hUaithnín's poems, though few survive, reflect the common themes of his time and place: loyalty to and trust in the Stuart cause, and a contempt for the new ascendancy and for those catholic priests who took the oath of abjuration in 1709. They include a lament for Sir Lucius O'Brien (d. 1717) and some less serious verses which give interesting and entertaining insights into the social and political life of Clare in his time.