many adherents. Thomas Müntzer, a leader of some non-peaceful groups of this sect, was active in this city. Within the borders of modern Thuringia the Roman Catholic faith only survived in the Eichsfeld district, which was ruled by the Archbishop of Mainz, and to a small degree in Erfurt and its immediate vicinity. Early modern period The modern German black-red-gold tricolour flag's first appearance anywhere in a German-ethnicity sovereign state, within what today comprises Germany, occurred in 1778 as the state flag of the Principality of Reuss-Greiz, a defunct principality in the modern state's borders. Some reordering of the Thuringian states occurred during the German Mediatisation from 1795 to 1814, and the territory was included within the Napoleonic Confederation of the Rhine organized in 1806. The 1815 Congress of Vienna confirmed these changes and the Thuringian states' inclusion in the German Confederation; the Kingdom of Prussia also acquired some Thuringian territory and administered it within the Province of Saxony. The Thuringian duchies which became part of the German Empire in 1871 during the Prussian-led unification of Germany were Saxe-Weimar-Eisenach, Saxe-Meiningen, Saxe-Altenburg, Saxe-Coburg-Gotha, Schwarzburg-Sondershausen, Schwarzburg-Rudolstadt and the two principalities of Reuss Elder Line and Reuss Younger Line. Free State of Thuringia In 1920, after World War I, these small states merged into one state, called the Free State of Thuringia (Freistaat Thüringen); only Saxe-Coburg voted to join Bavaria instead. Weimar became the new capital. The coat of arms of this new state was simpler than those of its predecessors. The Landtag of the newly established state first convened in 1920 in Weimar. Its deputies were elected for three years according to proportional representation, with a minimum voting age of 21. Between 1920 and 1932, under the Weimar Republic, six Landtag elections were held. Thuringia was one of the states where the Nazi Party first gained real political power. Wilhelm Frick was appointed Minister of the Interior in the state coalition government after the Nazi Party won six deputies to the Thuringian Landtag in the December 1929 election. In this position, he removed from the Thuringian police force anyone he suspected of being a republican and replaced them with men who were favourable towards the Nazis. He also ensured that, whenever an important position came up within Thuringia, a Nazi was given that post. Following the Nazi seizure of power in Berlin, the Landtag was formally abolished as a result of the