Following the arrival of 12000 Roman Catholics fleeing famine in Ireland, St David's was built as Cardiff's principal Catholic church in 1887, and it became a cathedral and seat of the Roman Catholic Archbishop of Cardiff in 1916.

The Cathedral was severely damaged by bombing in 1941, but following extensive restoration, it was re-opened in 1959. The Director of Music was a boy chorister at its inaugural service.

As Wales' National Cathedral, it remains the focal point for Catholic life in Cardiff, and the country as a whole. It is one of only three Roman Catholic Cathedrals in the UK which is associated with a choir school.