Thus, in 1597, civil war erupted, and Duke Charles was able to assume control over a large share of the powerful castles in the country, and in this manner achieved control over almost all the realm.
The problem was Finland, where Klaus Fleming's widow guarded Åbo castle.
But after psychological warfare, Charles and his followers managed 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."

When Sigismund found out about what had happened in Finland he lost his patience.
The King could not accept Duke Charles' disrespectful actions and decided to use force.
This decision eventually would cost him the Swedish crown.
In February 1598 Sigismund assembled an army consisting of merely 5,000 men, mostly Hungarian and German mercenaries.
A larger army had been proposed but had been dismissed because Sigismund expected Swedish forces to join him, and he also wished to avoid conflict with them.
The advisers and the King expected military support from Finland and Estonia (homes of the Swedish gentry formerly commanded by Fleming).
They also wanted help from Denmark–Norway and pro-Sigismund parts of Sweden.
The diplomat Laski was dispatched, but Denmark did not show any interest.
In May, Sigismund's men started to advance northwards.
The army gathered in Marienburg (Malbork), where the Livonian Jürgen Farensbach was appointed commander.
The army was to be transported from Danzig (Gdańsk) to Sweden on Swedish ships, but the Swedish Estates declined.
They refused to lend him ships as long as he stayed with a foreign army.
There was widespread suspicion against Sigismund and his Catholic warriors.
Thus the Estates promised to protect Duke Charles and the others who rebelled against the King.
Thus, in 1597, civil war erupted, and Duke Charles was able to assume control over a large share of the powerful castles in the country, and in this manner achieved control over almost all the realm. The problem was Finland, where Klaus Fleming's widow guarded Åbo castle. But after psychological warfare, Charles and his followers managed 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."
When Sigismund found out about what had happened in Finland he lost his patience. The King could not accept Duke Charles' disrespectful actions and decided to use force. This decision eventually would cost him the Swedish crown. In February 1598 Sigismund assembled an army consisting of merely 5,000 men, mostly Hungarian and German mercenaries. A larger army had been proposed but had been dismissed because Sigismund expected Swedish forces to join him, and he also wished to avoid conflict with them. The advisers and the King expected military support from Finland and Estonia (homes of the Swedish gentry formerly commanded by Fleming). They also wanted help from Denmark–Norway and pro-Sigismund parts of Sweden. The diplomat Laski was dispatched, but Denmark did not show any interest. In May, Sigismund's men started to advance northwards. The army gathered in Marienburg (Malbork), where the Livonian Jürgen Farensbach was appointed commander. The army was to be transported from Danzig (Gdańsk) to Sweden on Swedish ships, but the Swedish Estates declined. They refused to lend him ships as long as he stayed with a foreign army. There was widespread suspicion against Sigismund and his Catholic warriors. Thus the Estates promised to protect Duke Charles and the others who rebelled against the King.
Sigismund III Vasa