October 9 – Leif Erikson lands in L'Anse aux Meadows, Canada.
The Zubu khan surrenders to the Liao Dynasty.
January 25 – Werner, Margrave of the Nordmark, succeeds Lothair.
February 9 – Boleslaus III of Bohemia is restored to authority, with armed support from Bolesław I the Brave of Poland. In the following months, Boleslav's brothers Jaromir and Oldrich flee to Germany, and place themselves under the protection of Henry II, Holy Roman Emperor, while Boleslaus III of Bohemia orders the massacre of his leading nobles at Vyšehrad.
May 4 – Herman III, Duke of Swabia succeeds Herman II.
Vladivoj of Bohemia succeeds Boleslaus III.
Boleslaus IV succeeds Vladivoj of Bohemia.
Bolesław I of Poland annexes parts of present-day Slovakia (possible date).
Wilfred succeeds Abbot Oliva as count of Berga.
Sweyn I of Denmark begins his first invasion of England.
Humbert I becomes the first count of Savoy.
King Robert II of France invades Burgundy, but fails.
Robert II of France marries Constance of Arles.
Boleslaus I of Poland becomes duke of Bohemia and Moravia.
Stephen I of Hungary invades Transylvania, and organises the Diocese of Transylvania (possible date).
Deutz Abbey is founded at Deutz, by Heribert of Cologne.
Battle of Albesa: Troops of the Caliphate of Cordoba defeat the northern Christian armies.
Zacharias succeeds Philotheos, as Patriarch of Alexandria.
Construction of the Brihadeeswarar Temple, Thanjavur, Tamil Nadu, India, begins during the Chola Dynasty (Early Medieval period).
May 16 – Pope John XVII succeeds Pope Silvester II, as the 140th pope.
December 25 – Pope John XVIII succeeds Pope John XVII as the 141st pope.
Conrad II, Duke of Carinthia (d. 1039)
Edward the Confessor (approximate date) (d. 1066)
Emperor Jingzong of Western Xia
Frederick, Duke of Lower Lorraine (approximate date; d. 1065
Herleva, mother of William I of England (d. c. 1050)
Ibn Zaydún, Arabic poet (d. 1071)
Musharrif al-Daula, Buyid amir of Iraq (d. 1025)
January 25 – Lothair I, Margrave of the Nordmark
Rozala, Queen of France
May 4 – Herman II, Duke of Swabia
May 12 – Pope Sylvester II
November 6 – Pope John XVII
December 27 – Emma of Blois, Duchess and Regent of Aquitaine
At-Ta'i, the Abbasid Caliph in Baghdad from 974 to 991
Erik the Red
Gregory of Narek, Armenia poet, philosopher and theologian
Vladivoj of Bohemia
Didda, queen regnant of Kashmir
Year 1003 (MIII) was a common year starting on Friday (link will display the full calendar) of the Julian calendar.
(Text) CC BY-SA