Complex sentence: After World War I, the French state confiscated the castle in accordance with the 1919 Treaty of Versailles; since 2007 the premises are held by the Bas-Rhin "département".
Split into simpler sentences: After World War I, the French state confiscated the castle in accordance with the 1919 Treaty of Versailles. In 2007, ownership was transferred to the Bas-Rhin "département".