1822 AD., German States, Hannover, Georg IV, Clausthal mint, 1/12 Thaler, Welter 3020.

Königreich Hannover, Braunschweig-Calenberg-Hannover, Georg IV. (1820-1830), Münzstätte Clausthal, Münzmeister Ludwig August Bruel (1817-38), 1822 AD.,
3 Mariengroschen = 1/12 Thaler (21.5 mm / 3,16 g), Prägung 1.908.000 Stück, 3,24 g Prägegewicht, 0,437 Silber,
Obv.: KÖN. HANNOVERSCHE CONVENTIONS-MÜNZE. / 12 / EINEN / THALER / 1822 , Ausgabeland in Umschrift, Wertangabe in 3 Zeilen und darunter Jahreszahl.
Rev.: 160 EINE FEINE MARK / L. B. , springendes Roß nach links; Münzmeisterzeichen L. B. (Ludwig August Bruel).
Jaeger 21 ; AKS 43 ; KM 139 ; Welter 3020 .

The Kingdom of Hanover (German: Königreich Hannover) was established in October 1814 by the Congress of Vienna, with the restoration of George III to his Hanoverian territories after the Napoleonic era. It succeeded the former Electorate of Brunswick-Lüneburg (known informally as the Electorate of Hanover), and joined 38 other sovereign states in the German Confederation in June 1815. The kingdom was ruled by the House of Hanover, a cadet branch of the House of Welf, in personal union with the United Kingdom of Great Britain and Ireland until 1837. Since its monarch resided in London, a viceroy (usually a younger member of the British Royal Family) handled the administration of the Kingdom of Hanover.
The personal union with the United Kingdom ended in 1837 upon the accession of Queen Victoria because females could not inherit the Hanoverian throne, so her uncle became the ruler of Hanover. Hanover backed the losing side in the Austro-Prussian War and was conquered by Prussia in 1866, subsequently becoming a Prussian province.