Master of Arts, University Wales, 1954. Doctor of Letters (honorary), University Wales, 1993. Doctor of Philosophy, University Oxford, England, 1962.
Master of Arts, University Oxford, England, 1978.
Assistant lecturer in Welsh, U. Wales, Swansea, 1957-1960; lecturer in Welsh, U. Wales, Swansea, 1960-1968; reader in Welsh, U. Wales, Swansea, 1968-1974; professor in Welsh, U. Wales, Swansea, 1974-1978; professor of Celtic, Jesus College, U. Oxford, England, 1978-1996.
Fellow British Academy. Member American Academy Arts and Sciences (foreign honorary member), Royal Irish Academy (honorary member).
Married Sheila Mary Jeremy, July 31, 1957. Children: Sian Elisabeth, Nia Catrin.