Fighting broke out in Poznań on 27 December 1918 as a result of the sudden outburst of patriotic sentiment that followed the arrival of musician and patriot Ignacy Jan Paderewski the previous day. This spontaneous and initially chaotic fighting gradually became more organised. Once the city came under the control of the insurgents, similar events took place in the countryside. The insurgent units were commanded by Mgr. Stanisław Taczak and virtually took over the entire region in the first two weeks of January 1919, thanks to the determination and ingenuity of the Polish soldiers and to the Germans having been caught off-guard.

Gen. Józef Dowbor-Muśnicki, who had transformed the insurgent units into a regular army, came to Poznań in mid-January. All the territory that had been won, however, now had to be defended. Some 3,000 of those who fought in the uprising were killed with the fighting in Szubin, Rawicz and Zbąszyń being especially fierce.

A truce which brought the Wielkopolska insurgency to an end was concluded in Trier on 16 February 1919. The area the insurgents had won was included in the reborn republic under the terms of the peace treaty concluded in Versailles several months later. The success of the uprising was due to the skilful exploitation of propitious circumstances and to several generations having been raised in the spirit of combining patriotism with organic work.