An writer, teacher, librarian, lecturer, and poet, Jenkin was the first woman to lead the Gorsedh Kernow and was a founder member of Mebyon Kernow. She was the Grand Bard of the Gorsedh between 1997 and 2000, having already been the Deputy Grand Bard for three years.
Her bardic name is Bryallen, 'primose' in Cornish. She is a patron of Hypatia Trust.
Jenkin became a Cornish language bard in 1957. She was the first woman to hold the position of Deputy Grand Bard between 1994 and 1997, and then first woman to be Grand Bard between 1997 and 2000. She was the first woman in Wales, Cornwall or Brittany to hold that office. She sits on the Chair Archives and Publications sub-committee and chaird the Holyer an Gof Publications Awards committee, and is has been a member of the Historic Cornwall Advisory Group and Cornwall Archives Network.
By profession, Jenkin was a teacher. In Camborne, Jenkin taught English and acted as Librarian. She taught 'Cornish for Fun', and Certificate of Secondary Education Cornish in her own time, and helped to establish 'Cornish Studies for Schools' with the Local Education Authority. She re-established Cornwall School Library Association and was its first new chair.
She married Richard Jenkin (1925-2002), a fellow founding member of Mebyon Kernow and former Grand Bard, in 1956 at St Euny, Redruth.