Ó hEochaidh, Seán (1913–2002), folklore collector, was born 9 February 1913 in Croaghlin, Teelin, Co. Donegal, son of a fisherman. He was educated locally in Teelin national school and afterwards joined his father's fishing crew, working for several years as a fisherman.
From an early age he developed an interest in folklore and wrote down stories told by elderly people in his locality. In the autumn of 1935, at the age of 22, he was appointed by Séamus Ó Duilearga (qv) as the first full-time Irish folklore collector for the newly established Irish Folklore Commission in the Donegal Gaeltacht. He cycled around the country with an ediphone strapped to his back and twelve recording cylinders, collecting songs and stories. During the course of forty-three years he filled several hundred handwritten notebooks, a total of 50,000 manuscript pages, which are preserved in the folklore archives in UCD. His is the largest collection of folklore ever collected by one individual. He had a particular talent for placing interviewees at their ease and estimated that he had spoken to at least 1,500 people. Although he is best known for his collection of folklore in the Irish language, he also recorded and transcribed a substantial amount of material in English from Séamus Mac Amhlaoibh, a native Irish-speaker from Inis Caoil, Co. Donegal, who had settled in Inver, also in Donegal. In addition he collected a small amount of material in English from the last native Irish-speakers from Inishmurray, Co. Sligo.
He published widely: his writings included Sean-chaint Theilinn (1955) and Síscéalta ó Thír Chonaill, with an English translation (Fairy legends from Donegal) by Máire MacNeill (qv) (1977). Together with Proinsias Ó Conluain he was responsible for the publication of Rotha Móra an tSaoil (1959) by his father-in-law Micí Mac Gabhann (qv), which told the tale of Mac Gabhann's life from a hiring fair in Letterkenny, Co. Donegal, to the Klondike gold rush. The work won an award in 1958 and featured regularly on the post-primary curriculum. It was translated by Valentin Iremonger (qv) as The hard road to Klondike (1962). Ó hEochaidh was a regular contributor to the journal Béaloideas and frequently broadcast on Raidió na Gaeltachta. He assisted Heinrich Wagner (qv) in his research for the Linguistic atlas and survey of Irish dialects (1958–69), volume 4 of which is dedicated to Seán. He co-authored Sean-chaint na gCruach with Wagner for a German journal in 1963. At the invitation of Wagner he spent a brief period as a guest lecturer in the Celtic department in QUB during the 1960s.
When the Irish Folklore Commission was dissolved in 1971 he was assigned to the department of Irish folklore in UCD, where he remained till his retirement (1980). Internationally renowned for his collection of folklore, he was in correspondence with folklorists from a number of countries throughout Europe. He was conferred with an honorary D.Litt.Celt. by UCG in 1988. In the same year he was appointed an honorary member of the Folklore of Ireland Society. The following year he was elected president of Oireachtas na Gaeilge which was held in Glencolmcille, Co. Donegal. In 1995 he was named Donegal Person of the Year. He died 18 January 2002 in a nursing home in Falcarragh and is interred in Gortahork cemetery, Co. Donegal.
Seán married Micí Mac Gabhann's daughter Áine (d. 1995); the couple settled in Cloughaneely, Co. Donegal.