• In the second of the so-called "Bishops' Wars," pitting the Scottish church against the attempts of Charles I to strengthen episcopacy in Scotland, the Scots reaffirm the National Covenant of 1638 and invade northern England, occupying Northumberland and Durham. Hamstrung by the refusal of the Short Parliament to vote him money for an army, Charles makes peace at Ripon, but his promise to pay the Scots an indemnity forces him to summon the Long Parliament, which once again refuses to vote him money without a redress of grievances, and proceeds to pass a series of measures designed to sweep away what they saw as the encroachments of an increasingly despotic monarchy, setting England on the road to the English Civil War.
• The Thirty Years' War drags on in continental Europe. France nominally keeps up her four different wars in Belgium, Germany, Italy and Spain, but fighting is sporadic. Louis XIII himself presides over the successful siege of Arras in northern France, while in Italy French general Henri de Lorraine, comte de Harcourt defeats a Spanish army twice his size and captures Turin after a three month siege and countersiege. In Germany, Swedish general Johan Baner's thrust into Bohemia is checked at Saalfeld by the Austrians.
• The 13-year Revolt of the Catalans begins as Catalonian nationalists backed by the French rise in revolt against the centralizing efforts of the Castilian Spanish monarchy. Portugal, a Spanish possession since 1580, takes advantage of the confusion and secedes, proclaiming John of Braganza its new king John IV, although Spain will not officially recognize Portuguese independence until 1668.
• French troops under Pierre, duc de Villemor Seguier crush an unprising in Normandy of 20,000 peasants angered by an increase in the tax on salt.
• War breaks out between Dutch colonists on Manhattan Island and local Indian tribes. By 1645, nearly all natives living in the area that is now known as New York City will be exterminated.
• The Bay Psalm Book, a metrical translation of the Psalms published in Cambridge, Massachusetts by Stephen Daye, is the first book printed in North America.
• The Royal Academy of Turku, better known today as the University of Helsinki, is founded.

These people were born in 1640:

• English writer and poet Aphra Behn, one of the first professional female authors.
• Future Holy Roman Emperor Leopold I.
• French nobleman Philippe I, duc d'Orléans, progenitor of the house of Bourbon-Orléans that would later produce French king Louis-Philippe.
• Ivan Mazepa, future Cossack ruler of the Ukraine.
• Spanish priest and mystic Miguel de Molinos, founder of Quietism.
• Chinese author Pu Songling.
• Jacob Leisler, leader of an insurrection in colonial New York during the Glorious Revolution.
• French clergyman and explorer Louis Hennepin.
• French sculptor Antoine Coysevox.
• French Monk Dom Perignon, who helped develop modern champagne.

These people died in 1640:

• Flemish painting master Peter Paul Rubens.
• Sultan of the Ottoman Empire Murad IV, succeeded by Ibrahim I.
• Portuguese Jewish philosopher Uriel Acosta.
• English playwright Philip Massinger.
• English playwright John Ford (approximate).
• Chinese physician and author Zhang Jingyue.
• English clergyman and scholar Robert Burton, author of The Anatomy of Melancholy.
• Scottish poet William Alexander, earl of Stirling.
• Portuguese explorer Pedro Teixeira, an early voyager to the Amazon.

1639 - 1640 - 1641