|Centuries:||16th century – 17th century – 18th century|
|Decades:||1590s 1600s 1610s – 1620s – 1630s 1640s 1650s|
|Years:||1621 1622 1623 – 1624 – 1625 1626 1627|
- January 24 – Alfonso Mendez, appointed by Pope Gregory XV as Prelate of Ethiopia, arrives at Massawa from Goa.
- The Netherlands establish a trading colony at Kaohsiung on Taiwan.
- Thirty Walloon families settle in the New Netherland colony.
- Oslo is destroyed by fire. When rebuilt by Christian IV, it would be renamed Christiania.
- Claudio Monteverdi publishes Tancredi e Clorinda.
- Jean Louis Guez de Balzac publishes his Lettres.
- Bernardo de Balbuena publishes El Bernardo.
- Santa Rosalia makes a miraculous appearance during a plague in Palermo.
- Kalmia latifolia (mountain laurel) first recorded in America.
- Jakob Bartsch records the constellation Camelopardalis.
- Dr Challoner's Grammar School is founded.
- The Palace of Versailles is first built, as a hunting lodge.
- Chateau Cheverny begins construction.
- Pembroke College, Oxford founded.
- The Japanese Shogun expels Spanish from the land and severs trade with the Philippines
- Mail service begins in Denmark
- University founded in Bolivia
- War between England and Spain
- Cornelius Drebbel discover gases
- Cardinal Richelieu appointed by Louis XIII to be his advisor
- Henry Briggs publishes Arithmetica Logarithmica