How did the Congress of Vienna change the territory of Thuringia?

At the Congress of Vienna (1814–1815), the territorial map of the region was adjusted when Prussia received sections of Thuringia.2

While the Congress sought to create more integrated political entities across Germany, the region remained characterized by a complex patchwork of states, including various duchies and principalities. This resulted in anomalous frontiers that persisted for over a century; for instance, the city of Erfurt remained attached to the Prussian province of Saxony, and the region contained numerous enclaves and exclaves belonging to Prussian territories. These fragmented boundaries were not fully rationalized until after the administrative dissolution of Prussia following World War II.12