The 25th of November, or St Catherine's Day, 1596 saw the beginning of a series of events that was to become the Cudgel War, the largest peasant uprising in Finland and the last significant one in the Nordic Countries. The peasants decided to refuse the customary feeding and lodging of military units, and were prepared to take up arms to enforce this decision.
The revolt, started by Ostrobothnian peasants, spread over the breadth of Finland, from the shores of the Gulf of Bothnia in the west through Pirkanmaa and Häme to Savo in the east, under the leadership of Ostrobothnian landholder and land trader Jaakko Ilkka. On the last day of 1596, a decisive battle was fought in Nokia between the peasant rebels and army troops led by marshal Klaus Fleming. The rebels were beaten and scattered, and the peasants of Häme and Savo soon experienced the same fate.
At this point, the peasants of Northern Ostrobothnia rose up against the governance of Klaus Fleming. This second peasant rebellion reached southern Lapland in the north, and most peasants of Southern Ostrobothnia joined in again. In the battle of Ilmajoki, fought on the 24th of February 1597, Fleming's troops overwhelmed the peasants. The losses of this three-month uprising amounted to nearly 3 000 men, which was approximately 1.5 percent of Finland's population at the time.
Cudgel War was the last and the most widespread of the peasant uprisings caused by continuous demands heaped upon peasants by the military because of the war between Sweden (of which Finland was then a part of) and Russia.
More information about Cudgel War can be found for example here: http://www.uta.fi/~mo70181/fileet/cw.htm
Information om Klubbekriget finns på svenska till exempel här: http://www.kokkola.fi/historia/nuijasota/innehallsforteckning.htm
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