At the end of May 1598 Sigismund landed on Swedish soil at Avaskär.
The King opened peacefully by sending the diplomat Samuel Łaski to Kalmar for negotiations.
His task was to convince the city's commanders to open the gates.
However, the negotiations led nowhere.
Instead, the King took his soldiers and marched on Kalmar.
The army halted just outside the city.
The plan was to frighten the commanders into opening the gates.
To make his message even more terrifying, Sigismund threatened the city with severe punishments and to withdraw the nobility of all children in the city.
The propaganda worked well and Sigismund was able to make his long-desired entry on 1 August.
After the fall of Kalmar, Duke Charles found himself with major trouble on his hands.
The Polish Crown army attracted Swedish followers, and Stockholm, lacking military defence, was easily taken with the help of the nobility and officers of Götaland.
After this event, the cavalry of Uppland joined up, and new forces were mobilised in Finland and Estonia.

The morning of 25 September 1598 the armies clashed in a major engagement at the Battle of Stångebro.
Charles offered talks again but attacked in a mist while Sigismund's men were withdrawing to their camp, which resulted in only the mercenaries fighting since his Swedes refused to fight.
Duke Charles won a decisive victory that forced Sigismund to agree to harsh terms.
Charles demanded that the King send home his entire army but that he himself was to stay and await a Parliament.
Also, a number of Swedes who had sided with Sigismund, including his Council supporters, were captured.
These were later executed in the Linköping Bloodbath of 1600.

The peace agreement was sealed with a dinner between Charles and Sigismund at Linköping Castle.
The King, who was under pressure, fearing for his life without his army and having realised that he had lost the political battle, fled during the coming days to Poland in late 1598.
At the same time as the peace treaty was being signed in Linköping, conflicts were taking place in Dalarna.
There, a pro-Sigismund bailiff, Jacob Näf, had tried to raise up the Dalecarlians against Duke Charles.
Chaos ensued, Näf was executed, and the Dalecarlians set out on the so-called Neaf Campaign (1598), burning and killing down to Brunnbäck ferry.
In Västergötland, Carl Carlsson Gyllenhielm, illegitimate son of Duke Charles, defeated the rebellion.
At the end of May 1598 Sigismund landed on Swedish soil at Avaskär. The King opened peacefully by sending the diplomat Samuel Łaski to Kalmar for negotiations. His task was to convince the city's commanders to open the gates. However, the negotiations led nowhere. Instead, the King took his soldiers and marched on Kalmar. The army halted just outside the city. The plan was to frighten the commanders into opening the gates. To make his message even more terrifying, Sigismund threatened the city with severe punishments and to withdraw the nobility of all children in the city. The propaganda worked well and Sigismund was able to make his long-desired entry on 1 August. After the fall of Kalmar, Duke Charles found himself with major trouble on his hands. The Polish Crown army attracted Swedish followers, and Stockholm, lacking military defence, was easily taken with the help of the nobility and officers of Götaland. After this event, the cavalry of Uppland joined up, and new forces were mobilised in Finland and Estonia.
The morning of 25 September 1598 the armies clashed in a major engagement at the Battle of Stångebro. Charles offered talks again but attacked in a mist while Sigismund's men were withdrawing to their camp, which resulted in only the mercenaries fighting since his Swedes refused to fight. Duke Charles won a decisive victory that forced Sigismund to agree to harsh terms. Charles demanded that the King send home his entire army but that he himself was to stay and await a Parliament. Also, a number of Swedes who had sided with Sigismund, including his Council supporters, were captured. These were later executed in the Linköping Bloodbath of 1600.
The peace agreement was sealed with a dinner between Charles and Sigismund at Linköping Castle. The King, who was under pressure, fearing for his life without his army and having realised that he had lost the political battle, fled during the coming days to Poland in late 1598. At the same time as the peace treaty was being signed in Linköping, conflicts were taking place in Dalarna. There, a pro-Sigismund bailiff, Jacob Näf, had tried to raise up the Dalecarlians against Duke Charles. Chaos ensued, Näf was executed, and the Dalecarlians set out on the so-called Neaf Campaign (1598), burning and killing down to Brunnbäck ferry. In Västergötland, Carl Carlsson Gyllenhielm, illegitimate son of Duke Charles, defeated the rebellion.
Sigismund III Vasa