Oldenburg Free State of Oldenburg Freistaat Oldenburg Oldenburg 1918 Split into Lower Saxony, Schleswig-Holstein and Rhineland-Palatinate in 1946. Prussia Free State of Prussia Freistaat Preußen Berlin 1918 Abolished in 1947. Saxony Free State of Saxony Freistaat Sachsen Dresden 1918 Reuss People's State of Reuss Volksstaat Reuß Gera 1918–20 Merged into Thuringia in 1920.