|Covid-19|January 14 – The Hampton Court Conference is held between James I of England, the Anglican bishops and representatives of the Puritans. Work begins on the Authorized King James Version of the Bible and revision of the Book of Common Prayer.
June – Ottoman–Safavid War (1603–18): Shāh Abbas I of Persia's Safavid army captures the city of Yerevan from the Ottoman Empire after a siege. At this time the Shāh begins the expulsion of Armenians from Jolfa to New Julfa in his capital of Isfahan; more than 25,000 die during the exodus.
August 18 – England concludes the Treaty of London with Spain, ending the Anglo-Spanish War (1585–1604), an intermittent conflict within the Eighty Years' War.
September 1 – Sri Guru Granth Sahib, the religious text of Sikhism, is installed at Harmandir Sahib in Amritsar.
September 20 – Ostend is captured by Spanish forces under Ambrogio Spinola after a 3-year siege.
October 4 – Za Dengel, Emperor of Ethiopia, is killed in battle with the forces of Za Sellase, who restores his cousin Yaqob to the throne.
October 9 – The supernova which becomes known as Kepler's Supernova (SN 1604) is first observed from the northern parts of the Italian Peninsula. From October 17, Johannes Kepler begins a year's observation of it from Prague. There won't be another "naked-eye" supernova to be seen until 1987. As of 2017, this is the last supernova to be observed in the Milky Way.
November 1 – First recorded performance of William Shakespeare's tragedy Othello, at the Palace of Whitehall in London.
December 26 (St. Stephen's night) – First recorded performance of Shakespeare's tragedy King Lear, before King James I of England in the banqueting hall of Whitehall Palace.
The Sikh holy scripture Guru Granth Sahib is compiled and edited by Guru Arjan.
France begins settling Acadia, first successful French North American colony.
Before 1 October, Huntingdon Beaumont completes the Wollaton Wagonway, built to transport coal from the mines at Strelley to Wollaton just west of Nottingham, England, the world's oldest wagonway with provenance.
The Table Alphabeticall, the first known English dictionary to be organized by alphabetical ordering, is published.
First publication of Christopher Marlowe's play The Tragical History of Doctor Faustus, in London.
Lancelot de Casteau's L'Ouverture de cuisine published in Liège, including the first printed recipe for choux pastry.
According to legend, the vault of Christian Rosenkreuz is discovered.
The Papacy is expected to fall this year by Tobias Hess and Simon Studion according to their correspondence in 1597.
January 4 – Jakob Balde, German Latinist (d. 1668)
February 2 – Juan de Leyva de la Cerda, conde de Baños, Spanish noble (d. 1678)
February 24 – Arcangela Tarabotti, born Elena Tarabotti, Venetian nun and feminist (d. 1652)
March 10 – Johann Rudolf Glauber, German-Dutch alchemist and chemist (approximate date; d. 1670)
March 23 – Girolamo Colonna, Catholic cardinal (d. 1666)
April 5 – Charles IV, Duke of Lorraine (d. 1675)
April 9 – Duke Francis Henry of Saxe-Lauenburg (d. 1658)
Giovanni Giacomo Barbelli, Italian painter (d. 1656)
Frans Luycx, Flemish Baroque painter (d. 1668)
April 22 – Peter Venables, English politician (d. 1669)
April 28 – Joris Jansen Rapelje, Early Dutch settler in colonial North America (d. 1662)
May 1 – Louis, Count of Soissons (d. 1641)
May 4 – Sir Hugh Owen, 1st Baronet, English politician (d. 1670)
May 10 – Jean Mairet, classical French dramatist who wrote both tragedies and comedies (d. 1686)
May 17 – Vincent Baron, French Dominican theologian writer (d. 1674)
May 28 – Catherine of Brandenburg, Princess of Transylvania (1629–1630) (d. 1649)
June 4 – Claudia de' Medici (d. 1648)
June 10 – John Manners, 8th Earl of Rutland, English politician when he inherited the peerage (d. 1679)
June 17 – John Maurice, Prince of Nassau-Siegen (d. 1679)
June 28 – Heinrich Albert, German composer and poet (d. 1651)
June 30 – Margaret Elisabeth of Leiningen-Westerburg, Regent of Hesse-Homburg (d. 1667)
July 8 – Christiaen van Couwenbergh, Dutch painter (d. 1667)
July 25 – Dorothea Diana of Salm, German noblewoman (d. 1672)
August 3 – John Eliot, English puritan missionary (d. 1690)
August 4 – François Hédelin, abbé d'Aubignac, French author (d. 1676)
August 12 – Tokugawa Iemitsu, Japanese shogun (d. 1651)
August 16 – Bernhard of Saxe-Weimar, general in the Thirty Years' War (d. 1639)
August 25 – Shang Kexi, Chinese general (d. 1676)
September 13 – Sir William Brereton, 1st Baronet, English soldier and politician (d. 1661)
September 21 – Angelo Michele Colonna, Italian painter (d. 1687)
October 14 – Nils Brahe, Swedish soldier and younger brother of Per Brahe (d. 1632)
October 22 – Simon Le Moyne, French missionary (d. 1665)
Luigi Baccio del Bianco, Italian painter (d. 1657)
Krisztina Nyáry, Hungarian noblewoman (d. 1641)
November 3 – Osman II, Sultan of the Ottoman Empire (d. 1622)
November 6 – George Ent, English scientist (d. 1689)
Bernard of Offida, Italian saint (d. 1694)
Jacques Leneuf de La Poterie, Politician (d. 1689)
November 26 – Johannes Bach, German composer and musician (d. 1673)
December 7 – Ambrose Corbie, English Jesuit teacher (d. 1649)
December 10 – David Barry, 1st Earl of Barrymore, Irish noble (d. 1642)
Jasper Mayne, English dramatist (d. 1672)
Isaac Ambrose, English Puritan divine (d. 1664)
Menasseh Ben Israe
l, Jewish Rabbi (d. 1657)
Giovanni Battista Michelini, Italian painter (d. 1655)
Edward Pococke, English Orientalist and biblical scholar (d. 1691)
Abraham Bosse, French engraver and artist (d. 1676)
Egbert Bartholomeusz Kortenaer, Dutch admiral (d. 1665)
January 4 – Ferenc Nádasdy, Hungarian noble (b. 1555)
January 10 – Juliana of Lazarevo, Russian saint (b. 1530)
January 17 – Santino Garsi da Parma, Italian musician (b. 1542)
January 18 – Dorothy Catherine of Brandenburg-Ansbach, Burggräfin of Meissen (b. 1538)
January 23 – Hyujeong, Korean Seon master (b. 1520)
February 9 – Anne Russell, Countess of Warwick, wife of Ambrose Dudley, 3rd Earl of Warwick (b. 1548)
February 10 – Cyriacus Spangenberg, German theologian and historian (b. 1528)
February 13 – Catherine de Bourbon, French princess (b. 1559)
February 24 – Christoph Pezel, German theologian (b. 1539)
February 29 – John Whitgift, Archbishop of Canterbury from 1583 to his death (b. c. 1530)
March 4 – Fausto Paolo Sozzini, Italian theologian (b. 1539)
March 13 – Arnaud d'Ossat, French diplomat and writer (b. 1537)
April 1 – Thomas Churchyard, English author, secretary to Edward de Vere (b. 1520)
April 8 – Daniyal, Imperial Prince of the Timurid Dynasty, Viceroy of Deccan (b. 1572)
April 14 – Ernest Frederick, Margrave of Baden-Durlach (1584–1604) (b. 1560)
April 21 – Koide Hidemasa, Samurai (b. 1539)
April 25 – Pietro de' Medici, Italian noble (b. 1554)
May 5 – Claudio Merulo, Italian composer (b. 1533)
May 13 – Christine of Hesse (b. 1543)
May 26 – Godfrey Goldsborough, English bishop (b. 1548)
June 5 – Thomas Muffet, English naturalist and physician (b. 1553)
June 10 – Isabella Andreini, Italian actress (b. 1562)
June 21 – Jonathan Trelawny, English politician (b. 1568)
June 24 – Edward de Vere, 17th Earl of Oxford, Lord Great Chamberlain of England, poet and possibly playwright (b. 1550)
July 14 – Gaspar de Bono, Beatified Spanish Army veteran and Minim friar (b. 1530)
August 3 – Bernardino de Mendoza, Spanish military commander
August 8 – Horio Tadauji, Japanese warlord (b. 1578)
August 12 – John I, Count Palatine of Zweibrücken (b. 1550)
August 20 – Toda Kazuaki, Japanese samurai (b. 1542)
Hamida Banu Begum (b. 1527)
Otto Henry, Count Palatine of Sulzbach, Counts Palatine of Sulzbach (b. 1556)
August 30 – John Juvenal Ancina, Italian Oratorian and bishop (b. 1545)
September 10 – William Morgan, Welsh Bible translator (b. 1545)
September 12 – Louis Gunther of Nassau, Count of Nassau-Katzenelnbogen (b. 1575)
September 17 – Lucas Osiander the Elder, German pastor (b. 1534)
September 22 – Dorothy Stafford, English noble (b. 1526)
September 23 – Gabriel Vásquez, Spanish theologian (b. 1549)
October 4 – Za Dengel, Emperor of Ethiopia
Louis IV, Landgrave of Hesse-Marburg, German noble (b. 1537)
William Peryam, British judge (b. 1534)
October 18 – Igram van Achelen, Dutch statesman (b. 1528)
October 22 – Domingo Báñez, Spanish theologian (b. 1528)
October 25 – Claude de La Trémoille, French noble (b. 1566)
November – Thomas Storer, English poet (b. 1571)
November 21 – John Thynne, English landowner and politician (b. 1555)
November 23 – Olbracht Łaski, Polish alchemist (b. 1527)
November 29 – Ercole, Lord of Monaco, Monegasque noble (b. 1562)
December 3 – George Hastings, 4th Earl of Huntingdon, English nobleman (b. 1540)
December 22 – Kuroda Yoshitaka, Japanese Daimyo (b. 1546)
Early? – Thomas North, English translator of Plutarch (b. 1535)
Late – Richard Topcliffe, English politician and torturer (b. 1531)
Ma Shouzhen, Chinese courtesan, painter, poet, and composer (b. 1548)
1604 (MDCIV) was a leap year starting on Thursday (dominical letter DC) of the Gregorian calendar and a leap year starting on Sunday (dominical letter AG) of the Julian calendar, the 1604th year of the Common Era (CE) and Anno Domini (AD) designations, the 604th year of the 2nd millennium, the 4th year of the 17th century, and the 5th year of the 1600s decade. As of the start of 1604, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923.