1816 AD., German States, Posen, Grand Duchy, Friedlich Wilhelm III of Prussia, 1 Groschen, KM 30.

Großherzogtum Posen, Friedlich Wilhelm III. von Preussen (1797-1840), Münzstätte Berlin, 1816 AD.,
1 Groschen (20-21 mm / 2,36 g),
Obv.: gekrönter preussischer Adler auf ovalem Schild im Eichenkranz.
Rev.: 180 EINEN THALER / 1 / GROSCHEN / GR: HERZ: / POSEN / 1816 / A , siebenzeilig.
KM 30 ; AKS 53 ; Jäger 161 ; Gumowski 2479 .

The Grand Duchy of Posen, or the Grand Duchy of Poznań (German: Großherzogtum Posen; Polish: Wielkie Księstwo Poznańskie) was part of the Kingdom of Prussia, created from territories annexed by Prussia after the Partitions of the Polish-Lithuanian Commonwealth, and formally established following the Napoleonic Wars in 1815. Per agreements derived at the Congress of Vienna it was to have some autonomy. However in reality it was subordinated to Prussia and the proclaimed rights for Polish subjects were not fully implemented. The name was unofficially used afterward for denoting the territory, especially by Poles, and today is used by modern historians to describe different political entities until 1918. Its capital was Posen (Polish: Poznań). The Grand Duchy was formally replaced by the Province of Posen in the Prussian constitution of 5 December 1848.