|Centuries:||16th century – 17th century – 18th century|
|Decades:||1630s 1640s 1650s – 1660s – 1670s 1680s 1690s|
|Years:||1664 1665 1666 – 1667 – 1668 1669 1670|
- January 20 – Poland cedes Kyiv, Smolensk, and eastern Ukraine to Russia in the Treaty of Andrusovo that put a final end to the Deluge, and Poland lost its status as a Central European power.
- April 27 – The blind, impoverished John Milton sells the copyright of Paradise Lost for £10.
- June 12-17 – In the Raid on the Medway, a Dutch fleet under admiral Michiel de Ruyter burns Sheerness, sails up the River Medway, raids Chatham dockyards and escapes with the royal barge The Royal Charles.
- June 15 – The first human blood transfusion is administered by Dr. Jean-Baptiste Denys. He transfuses the blood of a sheep to a 15-year-old boy. (Though this operation is a success, a later patient dies from the procedure and Denys is accused of murder).
- June 20 – Dutch troops attack Royal Navy ships in London and Chatham and burn them.
- July 31 – Second Anglo-Dutch War ends: The Treaty of Breda ends the war. The treaty also recognizes Acadia as a French possession.
- October 18 – Brooklyn is chartered under the name Brueckelen by Mathias Nicolls, Governor of New Netherland.
- November 25 – Devastating earthquake rocks Caucasia, killing 80,000 people.
- Suleiman I becomes Shah of Persia.
- The Mogul Emperor Aurangzeb buys off the bandit Shivaji by making him a Rajah and allowing him to collect taxes.
- Robert Hooke demonstrates that the alteration of the blood in the lungs is essential for respiration.
- The War of Devolution begins, France invades Flanders and Free County.
- Louis XIV of France abolishes the Livre Parisis (Paris Pound) in favor of the much more widely used Livre Tournois (Tours Pound). He also designates Gabriel-Nicolas de la Reynie as first chief of "police" of Paris.
- French army uses grenadiers.
- Yohannes succeeds his father Fasildos as Emperor of Ethiopia.