Monarch – Charles XI
- The Treaty of Cardis formally discontinue the Russo-Swedish War (1656–58) with a Swedish victory and territorial gains.
- The Stockholms Banco becomes the first European bank to print banknotes.
26 June- Johanna Eleonora De la Gardie, poet (died 1708)
23 September - Christiana Oxenstierna, noblewoman notorious for marrying a partner of a different social class (died 1701)
10 December - Catherine of Pfalz-Zweibrücken (1661–1720), princess (died 1720)
18 December - Christopher Polhem, Swedish scientist, inventor and industrialist (died 1751)
19 November - Lars Kagg, military officer (born 1595)
1661 in Sweden Wikipedia
Events from the year 1661 in Sweden