Commissioned by the territorial estates as a Protestant church in 1578, it was designed by architect Christoph Windisch. Klagenfurt Cathedral is the oldest pilaster church in Austria. The 23 paintings on the walls and ceilings were painted over several times in the course of the years.
The Catholic Reformation Commission closed the cathedral in the year 1600. Four years later it was handed over to the Jesuits who managed the Jesuit school next door until the order was closed in 1773. A fire destroyed major parts of the church in the year 1723. Reconstruction did not begin until 1725. The Carinthian Baroque painter Josef Ferdinand Fromiller created the John of Nepomuk apotheosis. The church was raised to Cathedral status in 1787. The Cathedral was renovated in the 1890s and shines today in the lustrous Baroque colourfulness of the 18th century.
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