Saint Einion Frenin (Welsh: old Enniaun, mod. Sant Einion or Engan Frenin, lit. "Saint Einion the King"; Latin: Ennianus or Anianus) was a late 5th- and early 6th-century Welsh confessor and saint of the Celtic Church. His feast day was originally given as 9 February, although this had moved to the 10th or 12th by the 16th century and is no longer observed by either the Anglican or Catholic church in Wales.