This volume comprises a celebratory collection of articles presented to Séamus Mac Mathúna on the occasion of his 75^th birthday and launched at the 17^th International Symposium of Societas Celtologica Nordica held in Uppsala on 7–10 May 2020. The volume brings together papers contributed by Séamus' friends and colleagues in the broad areas of Literature, Language, Folklore and the History of Celtic Studies and includes an introductory appreciation of his contribution to the discipline. Literary papers deal with the hero and antihero in Indo-European literatures, Irish heroic literature, Irish voyage literature, Irish bardic poetry, seventeenth- and eighteenth-century Irish poetry and twentieth-century Irish literature. The Language section includes articles on Ogham inscriptions, Irish and Scottish dialectology, Irish place names and lexical compounds in Welsh. Papers in Folklore and the History of Celtic Studies deal with folktales, the question of native legend and borrowing, the translation of Irish material into Armenian, the collection of folklore in Co. Tyrone, Irish manuscripts in North America, lexicography in nineteenth-century Belfast, and connections between Gaelic and Arabic in the development of Celtic Studies as a discipline. The volume concludes with a comprehensive list of the publications of Séamus Mac Mathúna.