The saint to whom the cathedral is dedicated is Máedóc of Ferns (feast day 31 January), also known as Áedan or Aidan, who died in 626,[1] and not to be confused with St. Aidan of Lindisfarne (feast day 31 August), an Irish missionary who died in 651.

With the completion of the old Cathedral in 1809, Enniscorthy becomes the Episcopal Centre of the Diocese of Ferns.

A new cathedral, designed by Augustus Welby Pugin, reputedly based on Tintern Abbey in Wales, was built in 1843.

The cathedral was subsequently much renovated in line with reforms promulgated by the Second Vatican Council.

It was restored to its near original design in 1994 when authentic colours, materials and techniques were used.