When Graz became the residence of Innerösterreich from 1564 to 1619, the arts and designs were much influenced by many Italian masters, which came to provide the services of the archduke Karl II. Besides the fact that the art flourished, counter-reformation and the fear of Turkish forces were omnipresent. All available funds were taken to build a city to represent the archduke and his country. As a matter of fact, the defensive measures were completed and strengthened, which derailed finishes of certain buildings. The protestants and the catholic archduke tried to find agreements for both sides, so for financial support, Karl gave them more freedom to practice their religion. Maria, the archduke`s wife, married Karl in 1571 and supported him during the religious controversy. They also had fifteen children, the most famous son may have been Ferdinand II., who became the emperor of the holy roman empire in 1619. (he changed the residence from Graz to Vienna in 1620, which meant economic loss for the city). The whole appearance of Graz changed in these important years, the university was founded, a kind of bohemian way of life came up and the Jesuit order helped with the counter-reformation. The construction of Karl`s hunting lodge also falls in the time frame of this diploma thesis. Karlau castle was built from approximately 1580 to 1594 in the floodplain forests of Graz and was the archduke`s most popular destination for leisure activities: hunting, collecting arts and arms. Domenico dell`Aglio, an Italian master, was the builder of Karlau castle, which went through many transformations during the decades. Since Maria Theresia used the building to host prisoners of war, it is still a penal institution.