- Source: 1666 in Denmark
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- 1666 in Denmark
- Denmark
- 1666 in Norway
- List of wars between Denmark and Sweden
- History of Denmark
- 1666 in France
- Anne of Austria
- United States Virgin Islands
- Danish Americans
- List of ships of the line of Denmark
Events from the year 1666 in Denmark.
Incumbents
Monarch – Frederick III
Events
11 February; Denmark-Norway agrees an offensive alliance with the Dutch Republic against England, and enters the Second Anglo-Dutch War;
1 August – Anders Bording's Den Danske Mercurius, Denmark's first newspaper, is published for the first time.
= Undated
=Holmen Cemetery, the oldest cemetery in Denmark still in use, relocates to its current location in Østerbro
Births
22 February – Christian Christophersen Sehested, nobleman (died 1740)
16 June – Johan Conrad Ernst, architect (died 1750)
Deaths
23 September – Hannibal Sehested, diplomat (born 1609)
30 October – Iver Krabbe, nobleman and military officer (born 1602)