Acta Triadis Thaumaturgae

Acta Triadis Thaumaturgae (English title: "The Acts of a Wonder-Working Triad) concerns the lives of St. Patrick, St. Brigid, and St. Columba. It was published at Leuven in 1647 by John Colgan, O.F.M., mainly at the expense of Thomas Fleming, Archbishop of Dublin.

The full title runs as follows:

:"Triadis Thaumaturgæ, seu divorum Patricii, Columbæ, et Brigidæ, trium veteris et majoris Scotiæ, seu Hiberniæ, Sanctorum insulæ, communium patronorum acta, a variis, iisque pervetustis ac Sanctis, authoribus Scripta, ac studio R.P.F. Joannis Colgani, in conventu F.F. Minor. Hibernor, Stritior, Observ., Lovanii, S. Theologiæ Lectoris Jubilati, ex variis bibliothecis collecta, scholiis et commentariis illustrata, et pluribus appendicibus aucta; complectitur tomus secundus sacrarum ejusdem insulæ antiquitatum, nunc primum in lucem prodiens".

Want of funds alone prevented the publication of all the material which Colgan had transcribed and prepared for press, and from the catalogue of the manuscripts found in his cell after his death, it is evident that the great Irish hagiologist had given a detailed account of the labours of Irish missionaries in England, Scotland, Belgium, Alsace, Lorraine, Burgundy, Germany, and Italy. A small remnant of these unpublished volumes is now in the Franciscan Library, Dublin.

In 1652 Colgan begged his superiors to relieve him of the duties of guardian and professor, and he died at St. Anthony's, Leuven, on 15 January 1658.