From Wikipedia, the free encyclopedia
|Centuries:||16th century – 17th century – 18th century|
|Decades:||1590s 1600s 1610s – 1620s – 1630s 1640s 1650s|
|Years:||1618 1619 1620 – 1621 – 1622 1623 1624|
|1621 by topic:|
|Arts and Science|
|Architecture - Art - Literature - Music - Science|
|Lists of leaders|
|Colonial governors - State leaders|
|Birth and death categories|
|Births - Deaths|
|Establishments and disestablishments categories|
|Establishments - Disestablishments|
|Ab urbe condita||2374|
|English Regnal year||18 Ja. 1 – 19 Ja. 1|
— to —辛酉年十一月十九日
|- Vikram Samvat||1677–1678|
|- Shaka Samvat||1543–1544|
|- Kali Yuga||4722–4723|
|- Ǹrí Ìgbò||621–622|
|Japanese calendar||Genna 7
|Juche calendar||N/A (before 1912)|
|Julian calendar||Gregorian minus 10 days|
|Minguo calendar||291 before ROC
|Thai solar calendar||2164|
|Wikimedia Commons has media related to: 1621|
- February 9 – Papal Conclave of 1621: Pope Gregory XV succeeds Pope Paul V as the 234th pope.
- February 17 – Miles Standish is appointed as the first commander of Plymouth Colony.
- March 16 – Samoset, a Mohegan, visits the settlers of Plymouth Colony and greets them, "Welcome, Englishmen! My name is Samoset."
- March 22 – The Pilgrims of Plymouth Colony sign a peace treaty with Massasoit of the Wampanoags.
- March 31 – King Philip IV of Spain begins his 44-year rule.
- April – The Twelve Years' Truce between the Dutch Republic and the Spanish Empire expires, and both sides prepare to resume the Eighty Years' War.
- April 1 – The Plymouth, Massachusetts colonists create the first treaty with native Americans.
- April 5 – The Mayflower sets sail from Plymouth on a return trip to England.
- May 24 – The Protestant Union is formally dissolved.
- June 3 – The Dutch West India Company is founded.
- June 21 – Thirty Years' War: Twenty-seven Czech lords are executed on the Old Town Square in Prague as a consequence of the Battle of White Mountain.
- June 24 – Huguenot rebellions: Saint-Jean-d'Angély is taken after a 26 day siege by Royal forces.
- July 25 – Thirty Years' War: The Battle of Neu Titschein is fought; remnants of the Bohemian army manage to hold off the Imperial advance in Silesia for the moment.
- September–October – Battle of Khotyn: Polish troops hold off a large Ottoman army for over a month.
- August – Huguenot rebellions: Louis XIII besieges the Huguenot city of Montauban in the Siege of Montauban, but is forced to abandon his siege two months later.
- October – The Pilgrims of Plymouth Colony and Wampanoags celebrate a harvest feast (3 days), later regarded as the "First Thanksgiving", noted for peaceful co-existence.
- October 9 – The Treaty of Khotyn is signed between the Ottoman Empire and the Polish-Lithuanian Commonwealth, ending the First Polish-Ottoman War.
- November 11 – The ship Fortune arrives at Plymouth Colony, with 35 more settlers.
- December 31 – Thirty Years' War: The Peace of Nikolsburg is signed between Ferdinand II, Holy Roman Emperor and Gabor Bethlen, Prince of Transylvania. Bethlen agreed to renounce his claims to Hungary. In return Bethlen received several counties and lands along the eastern border of the Holy Roman Empire, and Moravia was granted religious freedom.
Date unknown 
- The Venezuelan city of Petare is founded by Spanish conquistadors as San Jose de Guanarito.
- The Swedish city of Gothenburg is founded by King Gustavus Adolphus of Sweden. The king also grants city rights to Luleå, Piteå and Torneå (Tornio). Riga falls under the rule of Sweden.
- The Dutch mathematician and astronomer, Willebrord Snel van Royen (1580–1626), discovers the famous law of refraction, also known as "Snellius' law".
- Tamblot starts the Tamblot Uprising
- The Dutch East India Company sends 2000 soldiers under the command of Jan Pieterszoon Coen to the Banda Islands in order to force the local inhabitants to accept the Dutch trade monopoly on the lucrative nutmeg, grown almost exclusively on the Banda islands. The soldiers proceed to massacre most of the 15,000 indigenous inhabitants.
- January 27 – Thomas Willis, English physician who made important contributions to anatomy, particularly of the brain and nervous system (d. 1675)
- February 2 – Johannes Schefferus, Alsatian-born humanist (d. 1679)
- February 21 – Rebecca Nurse, accused witch (d. 1692)
- March 31 – Andrew Marvell, English poet (d. 1678)
- April 1 – Guru Teg Bahadur, 9th Sikh Guru (d. 1675)
- April 25 – Roger Boyle, 1st Earl of Orrery, British soldier, statesman, and dramatist (d. 1679)
- July 6 – Jean de La Fontaine, French writer (d. 1695)
- July 22 – Anthony Ashley-Cooper, 1st Earl of Shaftesbury, British politician (d. 1683)
- August 19 – Gerbrand van den Eeckhout, Dutch painter (d. 1674)
- September 8 – Louis II de Bourbon, Prince de Condé, French general (d. 1686)
- December 23
- January 28 – Pope Paul V (b. 1550)
- February 15 – Michael Praetorius, German composer (b. 1571)
- February 28 – Cosimo II de' Medici, Grand Duke of Tuscany (b. 1590)
- March 31 – King Philip III of Castile (Philip II of Portugal) (b. 1578)
- April 1 – Cristofano Allori, Italian painter (b. 1577)
- April 15 – John Carver, first governor of Plymouth Colony
- May 11 – Johann Arndt, German theologian (b. 1555)
- May 15 – Hendrick de Keyser, Dutch architect and sculptor (b. 1565)
- June 8 – Anne de Xainctonge, French saint (b. 1567)
- June 21 – Kryštof Harant z Polžic a Bezdružic, Bohemian composer, soldier, and author (executed) (b. 1564)
- July 2 – Thomas Harriot, English astronomer and mathematician (b. c. 1560)
- July 10 – Charles Bonaventure de Longueval, Count of Bucquoy, soldier in Habsburg service (b. 1571)
- July 13 – Archduke Albert of Austria, Governor of the Low Countries (b. 1559)
- August 3 – Guillaume du Vair, French writer (b. 1556)
- August 15 – John Barclay, Scottish writer (b. 1582)
- September 17 – Robert Bellarmine, Italian saint (b. 1542)
- September 24 – Jan Karol Chodkiewicz, Polish military commander (b. 1560)
- September 25 – Mary Sidney, English writer, patroness and translator (b. 1561)
- October 8 – Antoine de Montchrestien, French dramatist and economist (b. c. 1575)
- October 16 – Jan Pieterszoon Sweelinck, Dutch composer (b. 1562)
- November 26 – Ralph Agas, English surveyor (b. c. 1540)
- December 13 – Katarina Stenbock, queen of Gustav I of Sweden (b. 1535)
- December 15 – Charles de Luynes, Constable of France (b. 1578)