The nobility of Finland, led by the Sigismund-appointed Governor, Klaus Fleming, rejects the decisions made by Duke Charles, sympathizing with the King and considering Charles a rebel.

As a counterattack, Charles instigates a rebellion against Fleming among the farmers in Ostrobothnia.

This dispute over the Swedish crown, combined with quarrels over social conditions, foreign policy, and religion (Roman Catholic versus Lutheran), lead to the last peasant revolt in Europe, the so-called Club War, or Cudgel War.

Fleming has managed to quell the revolt known as the Club War, thereby crushing the hopes of the Finnish peasants, but dies in April 1597.

A letter arrives from Sigismund’s headquarters in Poland stating that he will not accept Charles as regent.

The Duke then uses a tactic which his father had employed, namely to resign from office.

However, the response is not what Charles had been hoping for: the King accepts Charles’s resignation and invests complete power in the Privy Council.

Charles summons another illegal Parliament the same year, this time in Arboga, despite the difficult situation.

Only one of the Privy Councillors shows up.

The reason is that Charles’s goal of deposing Sigismund has now been revealed, and the men understand that a serious revolt is brewing.

When Duke Charles threatens the absent men with severe punishment, some of them lose courage.

Erik and Arvid Stenbock, Erik Larsson Sparre, Erik Brahe and Sten Banér flee immediately to Sigismund.

Duke Charles is thus able to assume control over a large share of the powerful castles in the country, and in this manner achieves control over almost all the Swedish Realm.

The problem is Finland, where Klaus Fleming’s widow guards Åbo castle, but after psychological warfare, Charles and his followers manage to take the castle in Turku (Swedish: Åbo).

It is said that when the Duke entered the castle chapel he saw Klaus Fleming’s body lying in a coffin.

He is said to have said: “Hadst thou now been alive, thy head would not have been in great safety.” Then Fleming’s widow Ebba Stenbock is said to have approached the Duke and responded: “If my late husband had been alive, Your Grace would never have entered herein.”