n 1800, the whole of Schleswig-Holstein was under Danish administration, with the exception of the Principality of Lübeck and the Duchy of Saxony-Lauenburg.
After the Gastein Convention in 1865, Schleswig and Lauenburg came under Prussian administration, Holstein under Austrian administration. The island of Arro, seven parishes south of Kolding and a small part around Ribe remained under Danish administration. In return Denmark gave up its claims to the royal enclaves on the west coast.
In 1867 Schleswig-Holstein became a Prussian province. With the transfer contract of 06.07.1920 the northern part of Schleswig was assigned to Denmark and the southern part to Germany. On 23.08.1946 Schleswig-Holstein was founded with the state capital Kiel.