On 27 December 1918 Poles in the Prussian Province of Posen took up arms, gained control of most of Greater Poland and created their own army; the Treaty of Versailles awarded almost the whole region to Poland. In 1939 it was incorporated into the Reich as the Wartheland. In January 1945, as Zhukov's armies advanced on Poznań and the Oder, the evacuation of German settlers was usually ordered at the last minute, in freezing cold, and Arthur Greiser left Poznań on 20 January.
1918
- 27 December 1918EventThe Greater Poland Uprising beginsOn 27 December 1918, a day after Paderewski arrived, shots rang out by the Hotel Bazar in Poznań. By night Poles held the station, post office and some forts.
- 27 December 1918 – 16 February 1919BattleThe Greater Poland Uprising27 December 1918 – 16 February 1919. Poles of the Prussian Province of Posen took up arms, seized most of Greater Poland and created an army of their own.