The Cudgel War (1596–1597) was a peasant uprising in Finland, then part of the Kingdom of Sweden, driven by widespread dissatisfaction with heavy taxes and abuses by the nobility. The peasants, primarily from Ostrobothnia, Northern Tavastia, and Savo, were overburdened by the "castle camp" system, where they were forced to house and support soldiers even after a 25-year war with Russia had ended. Additionally, harsh taxation, failed harvests, and exploitation by the nobility added to their grievances.
The conflict was also part of a broader power struggle between Duke Charles of Sweden and King Sigismund, who ruled both Sweden and Poland. Charles encouraged the Finnish peasants to revolt against the nobles, who supported Sigismund.
The uprising began in late 1596 and saw some early successes, but it was ultimately crushed by the professional, heavily-armed troops of Governor Klaus Fleming. After a series of defeats, including a final battle at Santavuori Hill, more than 1,000 peasants were killed, and their leader, Jaakko Ilkka, was executed.
In the aftermath, the revolt was remembered as a tragic and heroic stand against oppression. While it did not lead to immediate social change, the Cudgel War left a lasting legacy in Finnish history and literature, symbolizing the struggle of the common people against aristocratic exploitation.