The Archduke Ferdinand II. of Tyrol (1564-1595) was married to Philippine Welser, a daughter of the famous Augsburg merchant family. One of their two sons, Karl gained rule over the Margravate of Burgau in 1605. His father had designated Günzburg as his place of residence and already commissioned the Italian building master Alberto Lucchese to build a castle with a court church fitting their social rank in 1577. Travel journals from the time of around the beginning of the 16th century, describe a grand interior design; however a fire in 1703, restoration during the 19th century and bomb damage from during the Second World War have dramatically changed the appearance of this castle. Today the extensive complex houses finance offices and a local court.
The court church was built during the period 1579/80, and is one of the only well preserved churches from the late renaissance period in southern Germany. Interior details of this building style such as ionic columns and Corinthian capitals are very pleasing to the eye. In 1755, Joseph Dossenberger Junior was assigned to build the neighbouring Piarist College. The adjoining chapel, made in the late baroque Rococo style offered a church for the school. It is dedicated to the blessed José Calasanz, the founder of the Piarist order. Today the church is profaned; however, thanks to a sensitive restoration from 2004 until 2006, the building has been given back much of its former brilliance.