During the period of the Iberian Union ( 1580 – 1640 ), Portugal lost influence and power and made new enemies.

* 1584 – Theophilus Howard, 2nd Earl of Suffolk, English politician ( d. 1640 )

* 1640 – Amalia Catharina, German poet and composer ( d. 1697 )

Ahmed II was born at Topkapı Palace, Constantinople, the son of Sultan Ibrahim I ( 1640 – 48 ) by Valide Sultan Khadija Muazzez, and succeeded his brother Suleiman II ( 1687 – 91 ) in 1691.

In 1635 – 38, Pietro Boncompagni commissioned from Algardi a colossal statue of Philip Neri with kneeling angels for Santa Maria in Vallicella, completed in 1640.

* 1640 – Second Bishop's War: King Charles I's English army loses to a Scottish Covenanter force at the Battle of Newburn.

* 1695 – John Trenchard, English statesman ( b. 1640 )

* 1719 – Philippe de la Hire, French mathematician and historian ( b. 1640 )

* Yoel Sirkis ( 1561 – 1640 ), Polish posek and halakhist, known as " the Bach "

Barcelona had always been the stronghold of Catalan separatism and was the center of the Catalan Revolt ( 1640 – 52 ) against Philip IV of Spain.

** João IV ( 1640 – 1656 )

* Federico Colonna y Tomacelli, Prince of Butera, ( 1601-1641 ) Viceroy of Valencia, in Spain, 1640 – 1641, Viceroy of Catalonia, 1641.

* 1721 – Richard Lumley, 1st Earl of Scarbrough, English statesman ( b. 1640 )

* 1640 – Claude Fleury, French historian ( d. 1723 )

* 1578 – Agostino Agazzari, Italian composer and music theorist ( d. 1640 )

* 1640 – End of the Iberian Union: Portugal acclaims as King João IV of Portugal, ending 60 years of personal union of the crowns of Portugal and Spain and the end of the rule of the House of Habsburg ( also called the Philippine Dynasty ).

The city had a population of 21, 000 in 1640 before a plague in 1649 – 51 wiped out almost half of the city's inhabitants.

* 1640 – John Francis Regis, French saint ( b. 1597 )

* 1640 – ( baptism date ) – Aphra Behn, English playwright and novelist ( d. 1689 )

* 1640 – Robert Plot, English naturalist ( d. 1696 )

* 1716 – Charles de La Fosse, French painter ( b. 1640 )

* 1595 – Maciej Kazimierz Sarbiewski, Polish author and Latin Poet ( d. 1640 )

* On the morning of December 1, 1640 in Lisbon, a group of supporters of the Duke of Braganza party found Miguel de Vasconcelos, the hated Portuguese Secretary of State of the Habsburg Philip III, hidden in a closet, killed him and defenestrated him.

The absolutist party of the landowners and the Church, however, were not satisfied with this compromise, and they continued to regard Miguel as the legitimate successor to the throne on the grounds that according to the Portuguese succession rules ( approved by the Cortes after the 1640 Restoration ), Pedro had lost the right to the Portuguese crown, and therefore to choose a successor, when he took possession of a foreign crown ( Brazil ).

In the Spanish army, in 1635, Pedro de la Puente organized in Innsbruck ( Austria ) a body of dragoons, and in 1640 one was created in Spain as a tercio of a thousand dragoons armed with the arqabus.

Louis Bertrand ( saint ) | Louis Bertrand ( 1526-1581 ), portrait by Francisco de Zurbarán, 1640

Joseph's Coat Brought to Jacobby Giovanni Andrea de Ferrari, c. 1640.

The oldest known document in Maltese is " Il Cantilena " ( Maltese: Xidew il-Qada ) a poem from the 15th century written by Pietro Caxaro, and the first known Maltese dictionary was written by the French Knight Francois de Vion Thezan Court in 1640.

* 1707 – Athénaïs de Montespan, French mistress of Louis XIV of France ( b. 1640 )

* 1640 – Philippe de la Hire, French mathematician and astronomer ( d. 1719 )

Magdalen with the Smoking Flame, by Georges de La Tour ( c. 1640 )

* 1640 – Willem de Vlamingh, Flemish sea captain ( d. c. 1698 )

Some add the detail of Cupid aiming at the sea-god with his bow, as in the painting of Laurent de la Hyre ( 1640 / 4 ) in the J. Paul Getty Museum and that of Jacques Dumont le Romain ( 1726 ) at the Musée des beaux-arts de Troyes.

A low seventh string was supposedly added in France to the bass viol by Monsieur de Sainte-Colombe ( c. 1640 – 1690 ), whose students included the French gamba virtuoso and composer Marin Marais.

pt: Década de 1640

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* December 13 – Charles de La Fosse, French painter ( b. 1640 )

The geographic limits of Portugal are fixed permanently, with the exception of São Félix de Galegos, lost in 1640 and Olivenza, lost in 1801.

** Isaac Manasses de Pas, Marquis de Feuquieres, French soldier ( d. 1640 )

* April 21 – Philippe de la Hire, French mathematician and astronomer ( b. 1640 )

In 1648, after Portugal has regained its independence from the Spanish rulers in 1640, a large Portuguese force from Brazil under the command of Salvador Correia de Sá retook Luanda, leading to the return of the Portuguese in large numbers.

As a musical form, however, the so-called French overture begins with the court ballet and operatic overtures of Jean-Baptiste Lully, which he elaborated from a similar, two-section form called Ouverture, found in the French ballets de cour as early as 1640.

The theorem is named after Pierre de Fermat, who stated it in 1640.

Pierre de Fermat first stated the theorem in a letter dated October 18, 1640, to his friend and confidant Frénicle de Bessy as the following: p divides a < sup > p − 1 </ sup > − 1 whenever p is prime and a is coprime to p.