Irish missionaries out of monasteries in Ireland and Scotland were instrumental in the spread of Christianity in Continental Europe during the Middle Ages. Of special importance in Austria is Saint Koloman of Stockerau killed near Vienna in 1012. This Irish monk of royal lineage killed at Stockerau while on pilgrimage to Jerusalem has been patron saint of Austria until 1663. During the 11th and the 12th century, Iro -Schotten Monasteries sprang up, intended exclusively for monks from monasteries in Ireland and the now Scottish isles. The famous Scottish Monastery of St. Jacob at Ratisbon, built around 1090 by Burgrave Otto of Ratisbon in Ratisbon, became the mother-house of a series of other Scots Monasteries, among them Our Blessed Lady at Vienna built in 1158.
Exterior
The first church was a three-aisled Romanesque pillar church with a single apse, destroyed by a fire in 1276. An earthquake circa 1443 greatly damaged the existing church on the site. Restorations were completed by 1449 but poorly done, due to lack of money, and on 21 May 1634, the roof collapsed in full view of Ferdinand II, Holy Roman Emperor. The collapse of the tower, struck by a lightning bolt in 1638, was seized as an opportunity to completely rebuild the church in Baroque style. From 1638–1641, the reconstruction was undertaken by the architects Carlo Antonio Carlone and Marco Spazzio. From 1643–1648, Andrea Allio the Old, Andrea Allio the Young and Silvestro Carlone reworked the nave and the west side. In the process, the length of the church was somewhat reduced, with the result that the tower no longer stands directly beside the basilica. After the Turkish siege, the church was restored again. As the baroque west tower was barely higher than the facade itself, its extension has often been discussed, but these plans have never come to fruition. The choir tower was dedicated only in the year 1893.
Interior
Inside, the church is now in high-baroque style with several chapels. Joachim von Sandrart provided the church with a new altar-piece, which today is kept in the prelates' hall. Between 1883–1889, the high altar was built after sketches of Heinrich Ferstel, with Innsbruckglass mosaics by Michael Riese. Julius Schmid was artist for the fine ceiling paintings.
After composer Joseph Haydn died in Vienna, a great memorial service was held in the Schottenkirche on 15 June 1809, at which Mozart’s Requiem K.626 was performed.