- Swedish occupation of Landskrona and Helsingborg in Danish Scania.
16 May - Action of 16 May 1644
1 July - Battle of Colberger Heide
13 October - Battle of Fehmarn (1644)
23 November - Battle of Jüterbog
- Queen Christina is declared to be of legal majority and the regency government is dissolved.
December 4 - Battle of Bysjön
- A new sumptuary law bans the use of textiles, laces and ribbons of gold and silver for clothing, as well as engagement- and baptism parties: the law is not respected and is replaced in 1664.
Births
7 February - Nils Bielke, member of the High Council of Sweden, military and politician (died 1716)
26 July - Clas Fleming (admiral), admiral and administrator involved in the development of a formal management structure for the Royal Swedish Navy under King Gustav II Adolf and Queen Christina (born 1592)
21 April - Torsten Stålhandske, Finnish officer in the Swedish army during the Thirty Years' War (born 1593)
