The chapel´s north-south axis is dating back to the 9th or 10th century.
The tomb of the noble Stahemberger Dynasty, the former charnel house, is probably a part of Wartberg´s oldest church.
Documents prove the existence of the ancient Saint Michael´s Chapel located exactly on the south-north axis, today´s mortuary. The late Gothic part of the building, the so-called Dionysius Chapel facing north, was added to the former chapel in 1508 and - by mistake - also called Saint Michael´s Chapel.