Ex qua die arcano
Ex qua die arcano is the incipit of the 4 March 1853 apostolic letter by which Pope Pius IX decreed the reestablishment of the [episcopal hierarchy in the Netherlands]. Through it, the administrative area formerly known as the Dutch Mission was divided into dioceses. Roman Catholic [Archdiocese of Utrecht|Utrecht] was raised, once more, to a Roman Catholic archdiocese, and received the four suffragan dioceses of Roman [Catholic Diocese of Haarlem-Amsterdam|Haarlem], Roman Catholic [Diocese of 's-Hertogenbosch|'s-Hertogenbosch], Breda, and Roermond.