The Grand Duchy of Posen, was part of the Kingdom of Prussia, created from territories annexed by Prussia after the Partitions of Poland, 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. The Grand Duchy was formally replaced by the Province of Posen in the Prussian constitution of 5 December 1848.
Originally part of the Kingdom of Poland, this area largely coincided with Greater Poland. The mid-17th century brought devastation from invading Swedish forces during "the Deluge". The eastern portions of the territory were taken by the Kingdom of Prussia during the Partitions of Poland; during the first partition (1772), Prussia took just the Netze District, the portion along the Noteć river. Prussia added the remainder during the second partition in 1793. Prussia briefly lost control during the Kościuszko Uprising in (1794).
It was initially administered as the province of South Prussia. The Poles were the primary ally of Napoleon Bonaparte in Central Europe, participating in the Greater Poland Uprising of 1806 and supplying troops for his campaigns. After the defeat of Prussia by Napoleonic France, the Duchy of Warsaw was created by the Treaty of Tilsit in 1807.
According to the Congress of Vienna, put into action after the fall of Napoleon in 1815, parts of the Prussian territory partitioned from Poland was passed on to Russia. From the remainder the Grand Duchy of Posen was to be created, that was to be a nominally autonomous province under Hohenzollern rule with the rights of "free development of Polish nation, culture and language", and was outside the German Confederation. Originally the Grand Duchy was to include Chełmno and Toruń. Prussia however disregared this promise from Congress of Vienna. At this time the city of Poznań was the administrative centre and the seat of the Statthalter "Prince Antoni Henryk Radziwiłł of Poznań". In reality the actual administrative power over the region was awarded by Prussia to provincial upper-president Joseph Zerboni di Sposetti, who was a Prussian of German ethnicity.
At the beginning of the Prussian takeover of Polish territories, the discrimination and repression of Poles consisted of reducing their access to education and the judicial system. Prussian officials identified Germanisation as the progress of higher culture over a lower one. As a result the local administration discriminated against Poles. After 1824 attempts to Germanise the school system were hastened and the government refused to establish a Polish university in Poznań. Polish politicians issued protests against Prussian policies and a secret, patriotic Polish organisation was founded called Towarzystwo Kosynierów (Society of Scythemen). Resistance activity of Poles resulted in reaction from Berlin, where a trial was held in connection to links between Poles from the Grand Duchy with Poles from Russian-ruled Congress Poland.
The 1830 November Uprising within Congress Poland against the Russian Empire was significantly supported by Poles from the Grand Duchy. Afterward, the Prussian administration under Oberpräsident Eduard Flottwell known for his anti-Polonism introduced a stricter system of repression against the Poles. Prussian authorities attempted to expel Poles from administration to weaken the Polish nobility by buying its lands, and, after 1832, the role of the Polish language in education was significantly repressed. Local self-government in the landed estates of land-lords, which was dominated by Polish nobility, was abolished, and instead the Prussian state appointed commissioners. Monasteries and their assets were confiscated by Prussia. The office of the governor (Statthalter) was abolished. Germanisation of institutions, education as well through colonisation was implemented.
Before 1848 repressions intensified in the Duchy, censorship was strengthened, settlers of German ethnicity were brought in. Large patriotic demonstrations were held in memory of Antoni Babiński, a member of the Polish Democratic Society. He had been wounded by a gunshot, when the Prussian gendarme attempting to arrest him, engaged in a fight with him. Babiński was then captured, sentenced to death and executed in Poznań. His public execution in February 1847 was accompanied by public mourning. Cloth soaked in his blood and other remains were distributed as national relics. Large prayers were held in his memory, often against orders of Prussia. Members of such gatherings were persecuted by police. At the same time the national self-awareness grew among the rural population of Polish and German ethnicity alike. Whereas two thirds of the grand ducal population identified as ethnically Polish (mostly in the centre, south and east), one third envisioned themselves as being of German ethnicity. Anti-Prussian sentiment grew as response to policy of Germanisation and repression by Prussian authorities and the conspiracy organisation called Związek Plebejuszy found a potent ground. It was led by bookseller Walenty Stefański, poet Ryszard Berwiński and lawyer Jakub Krauthofer-Krotowski.
Frankfurt Parliament of 1848 and the Duchy
During the Revolutions of 1848 the Frankfurt Parliament attempted to divide the grand duchy, no part of the German Confederation, into two parts: the Province of Posen, which would have been annexed to a to-be-created united Germany, and the Province of Gniezno, which would have remained outside Germany, but because of the protest of Polish parliamentarians these plans failed and the integrity of the grand duchy was preserved. However, on February 9, 1849, after a series of broken assurances, the Prussian administration renamed the grand duchy to the Province of Posen. However the Prussian Kings up to William II, German Emperor still held the title "Grand Duke of Posen" until 1918.