1040
Year 1040 was a leap year starting on Tuesday of the Julian calendar.
Events
By place
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.
- August 22–23 – Battle at Brůdek: Duke Bretislav I of Bohemia defeats the German forces under King Henry III in the Bohemian Forest.
- Peter Delyan leads a rebellion against the Byzantine Empire and is proclaimed by the Bulgarian nobles as emperor Peter II in Belgrade.
- The Emirate of Sicily is divided and fragmented into small fiefdoms. The Arab nobles of Palermo restore the regime of the Kalbids.
Britain
- March 17 – King Harold Harefoot dies at Oxford at the age of 24. His illegitimate son Ælfwine Haroldsson is left in the care of his grandmother, Ælfgifu of Northampton.
- June 17 – Harthacnut lands at Sandwich and reclaims the throne of England which had been taken by Harald Harefoot in 1035.
- August 14 – King Duncan 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 led by Sultan Mas'ud I at Dandanaqan, a fortress city in the desert near Merv. Ghaznavid commanders Ali Daya and Begtoghdi are blamed for the defeat and executed.
By topic
Religion
- Weihenstephan Abbey 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
- July 12 – Yun Kwan, Korean general
- Adelaide of Hungary, duchess of Bohemia
- Alan Rufus, Norman nobleman
- Alfonso VI, king of León and Castile
- Al-Mu'tamid ibn Abbad, Abbadid emir of Seville
- Arnold of Soissons, French bishop
- Blessed Gerard, founder of the Knights Hospitaller
- Bonfilius, bishop of Foligno
- Conrad I, count of Luxembourg
- Ernulf, French Benedictine monk and bishop
- Gebhard III, bishop of Constance
- Geoffrey III, Count of Anjou, French nobleman
- Géza I, king of Hungary
- Guérin of Aumale, Founder of House of Aumale
- Guglielmo Embriaco, Genoese merchant
- Haziga of Diessen, German countess
- Harald III, king of Denmark
- Herman I, margrave of Baden
- Hugh I, French nobleman
- Hugh of Die, French bishop
- Ibn Aqil, Persian theologian and jurist
- Ida of Lorraine, French countess
- Ivo of Chartres, French bishop
- Ladislaus I, king of Hungary
- Oddone Frangipane, Italian monk and hermit
- Odo I of Furneaux, French nobleman
- Roger I of Sicily, Norman nobleman
- Sikelgaita, Lombard duchess of Apulia
- Wulfnoth Godwinson, English nobleman
- Xiao Guanyin, Chinese empress consort of the Liao dynasty
- Zayn al-Din Gorgani, Persian physician
Deaths
- January 17 – Mas'ud I, Ghaznavid sultan
- 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
- August 14 – Duncan I, king of Scotland
- October 1 – Alan III, duke of Brittany
- Abu Hashim al-Hasan, Zaidi imam and ruler of Jemen
- Abu Nasr Mushkan, Persian statesman
- Ali Daya, Ghaznavid commander-in-chief, executed
- Begtoghdi, Ghaznavid commander-in-chief, executed
- Bertha of Milan, Lombard duchess
- Dietrich I, bishop of Meissen
- Gilbert, Count of Brionne, Norman nobleman
- Helias of Cologne, Irish abbot and musician
- Hugh, Italian nobleman
- Hugh I, count of Empúries and Peralada
- Ibn al-Haytham, Arab astronomer
- John V, duke of Gaeta
- Maria of Amalfi, Lombard duchess
- Nikephoros Dokeianos, Byzantine general
- Unsuri, Persian poet and writer
- Yeshe-Ö, Tibetan lama-king