1040

Year 1040 (MXL) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar.

Europe

 * Spring – Nikephoros Dokeianos, Byzantine governor of the Catepanate of Italy, is murdered by Lombard rebels at Ascoli. He is replaced by Michael Dokeianos, who arrives in November with a Varangian army.
 * The Emirate of Sicily is divided and fragmented into small fiefdoms. The Arab nobles of Palermo restore the regime of the Kalbids (approximate date).
 * August 22–23 – Battle of Brůdek: Duke Bretislav I of Bohemia defeats the German forces under King Henry III (the Black) in the Bohemian Forest.
 * Peter Delyan leads a rebellion against the Byzantine Empire and is proclaimed by the Bulgarian nobles as emperor (tsar) Peter II in Belgrade.

Britain

 * March 17 – King Harold Harefoot dies at Oxford at the age of 24. His illegitimate son Ælfwine Haroldsson is left in his grandmother's care, Ælfgifu of Northampton.
 * June 17 – Harthacnut lands at Sandwich and reclaims the throne of England which has been taken by Harald Harefoot (see 1035).
 * August 14 – King Duncan I is killed in battle against his first cousin and rival Macbeth, who succeeds him as king of Scotland.

Islamic world

 * May 23 – Battle of Dandanaqan: The Turkmen Seljuqs defeat the Ghaznavid forces (50,000 men) led by Sultan Mas'ud I at Dandanaqan, a fortress city in the desert near Merv.

Religion

 * Weihenstephan Abbey (Kloster Weihenstephan) in Germany, founds the oldest operating brewery.
 * The Shalu Monastery is founded by the Buddhist monk Chetsun Sherab Jungnay in Tibet.

Births

 * February 22 – Rashi, French rabbi and writer (d. 1105)
 * July 12 – Yun Kwan, Korean general (d. 1111)
 * Adelaide of Hungary, duchess of Bohemia (d. 1062)
 * Alan Rufus, Norman nobleman (approximate date)
 * Alfonso VI, king of León and Castile (approximate date)
 * Al-Mu'tamid ibn Abbad, Abbadid emir of Seville (d. 1095)
 * Arnold of Soissons, French bishop (approximate date)
 * Blessed Gerard, founder of the Knights Hospitaller (d. 1120)
 * Bonfilius, bishop of Foligno (approximate date)
 * Conrad I, count of Luxembourg (approximate date)
 * Elimar I (or Egilmar), count of Oldenburg (d. 1112)
 * Ernulf, French Benedictine monk and bishop (d. 1124)
 * Gebhard III, bishop of Constance (approximate date)
 * Geoffrey III, French nobleman (approximate date)
 * Géza I (Magnus), king of Hungary (approximate date)
 * Guglielmo Embriaco, Genoese merchant (d. 1102)
 * Haziga of Diessen, German countess (approximate date)
 * Harald III, king of Denmark (approximate date)
 * Herman I, margrave of Baden (approximate date)
 * Hugh I, French nobleman (approximate date)
 * Hugh of Die, French bishop (approximate date)
 * Ibn Aqil, Persian theologian and jurist (d. 1119)
 * Ida of Lorraine, French countess (approximate date)
 * Ivo of Chartres, French bishop (approximate date)
 * Ladislaus I, king of Hungary (approximate date)
 * Oddone Frangipane, Italian monk and hermit (d. 1127)
 * Odo I (or Eudes), French nobleman (d. 1086)
 * Roger I, Norman nobleman (approximate date)
 * Sikelgaita, Lombard duchess of Apulia (d. 1090)
 * Wulfnoth Godwinson, English nobleman (d. 1094)
 * Xiao Guanyin, empress of the Liao Dynasty (d. 1075)
 * Zayn al-Din Gorgani, Persian physician (d. 1136)

Deaths

 * January 17 – Mas'ud I, Ghaznavid sultan (b. 998)
 * March 3 – Cunigunde, Holy Roman Empress
 * March 17 – Harold Harefoot, king of England
 * May 29 – Renauld I, French nobleman
 * June 21 – Fulk III, French nobleman (b. 970)
 * August 14 – Duncan I, king of Scotland
 * October 1 – Alan III, duke of Brittany (b. 997)
 * Abu Hashim al-Hasan, Zaidi imam and ruler of Jemen
 * Abu Nasr Mushkan, Persian statesman (or 1039)
 * Ali Daya, Ghaznavid commander-in-chief
 * Begtoghdi, Ghaznavid commander-in-chief
 * Bertha of Milan, Lombard duchess (approximate date)
 * Dietrich I, bishop of Meissen (approximate date)
 * Gilbert, Norman nobleman (approximate date)
 * Helias of Cologne, Irish abbot and musician
 * Hugh, Italian nobleman (approximate date)
 * Hugh I, count of Empúries and Peralada
 * Ibn al-Haytham, Arab astronomer (approximate date)
 * John V, duke of Gaeta (approximate date)
 * Maria of Amalfi, Lombard duchess (approximate date)
 * Nikephoros Dokeianos, Byzantine general
 * Unsuri, Persian poet and writer (or 1039)
 * Yeshe-Ö, Tibetan lama-king (approximate date)