went to Hesse-Hanau and the Principality of Birkenfeld was awarded to the Grand Duchy of Oldenburg for the contribution of Peter I, then regent of Oldenburg, to the military effort against Napoleon. By 1866 Birknefeld had become entirely enclaved within the Prussian Rhine Province, as Lichtenberg had been sold to Prussia in 1834 and Meisenheim had been annexed following the Austro-Prussian War. Under Oldenburg rule, the new palatial castle, which is now the district administration's seat, was built in 1821. Not only was this built, but so were further buildings in the Governmental Quarter (), such as the infantry barracks (until 1963, a Gymnasium building, now the local office for the regulation of expenditures caused by stationed forces), which to this day characterize the town's appearance with their Classicist style from Oldenburg times. On 1 April 1937, during the Nazi period, the Birkenfeld region was transferred to the Prussian Rhine Province; it was merged with the (roughly "remnant district") of St. Wendel-Baumholder to form the Birkenfeld District. (The of St. Wendel-Baumholder was what had been the Principality of Lichtenberg until 1834, with the designation as a having arisen after part of its territory, including St. Wendel itself, had been detached to form part of the Territory of the Saar Basin established under the terms of the Treaty of Versailles). After the Second World War, Birkenfeld belonged to the French Occupation Zone, and since 1946, it has been a district seat in Rhineland-Palatinate. Religion In 2008, 50% of the town's inhabitants were Evangelical and 31% were Catholic. Besides these two biggest groups, there are an Evangelical Free Church congregation (Baptists), the Mennonite Brethren Church, a New Apostolic church and the Jehovah's Witnesses. Politics Birkenfeld has been a district seat since 1947 and forms together with 30 other municipalities a Verbandsgemeinde, a kind of collective municipality, called the Verbandsgemeinde of Birkenfeld. Town council The council is made up of 22 council members, who were elected by proportional representation at the municipal election held on 25 May 2014, and the honorary mayor as chairman. The municipal election held on 25 May 2014 yielded the following results: BFL is Birkenfelder Freie Liste (“Birkenfeld Free List”). BfB is Bürger für Birkenfeld (“Citizens for Birkenfeld”). Mayors Birkenfeld's mayor is Miroslaw Kowalski (CDU), re-elected in 2019. His predecessor was Peter Nauert (CDU). Peter Nauert was the first mayor ever to be elected by direct vote by the