|Covid-19|April – King Baldwin I of Jerusalem captures Arsuf and Caesarea (in May).
Crusade of 1101: Second wave of European crusaders attempt to cross Anatolia to reach the Kingdom of Jerusalem. They are heavily defeated by the Seljuq troops of Kilij Arslan I at Heraclea Cybistra and just a handful of knights manage to reach Palestine.
June 20 – Robert Curthose, duke of Normandy, lands at Portsmouth to try to take the throne of England from his brother, Henry. In July that year, he signs the Treaty of Alton, giving up his claim to the Anglo-Norman throne and establishing Henry I as King of England.
June 22 – At birth, Roger II becomes count of Sicily and duke of Calabria. His mother becomes regent.
August – The troops of the Almoravid ruler, Yusuf ibn Tashfin, besiege Valencia, which is defended by Jimena Díaz, widow of El Cid. The city holds until May 1102.
Fall – Countess Mathilda takes Ferrara.
November – At the death of his father, Welf I, Duke of Bavaria, Welf II, Duke of Bavaria becomes duke of Bavaria.
The County of Berg, Germany is established.
A vast compilation of Liao, Korean, and Song Buddhist writings is completed.
April 19 – Canute II of Denmark is canonized.
At the death of antipope Theodoric, the partisan of the Holy Roman Emperor choose Albert as the new antipope.
Establishment of the Fontevraud Abbey.
Helena of Skövde, Swedish local saint (d. 1160)
Adrian Alabastra (from Flicker by L.J. Tryton); May 15
June 22 – Count Roger I of Sicily (b. 1031)
Conrad, King of Germany and Italy (b. 1074)
Hugh d'Avranches, Earl of Chester
September – Ida of Austria, Austrian duchess and crusader (b. 1055)
October 6 – Bruno of Cologne, German founder of the Carthusian order
October 18 – Hugh of Vermandois, son of Henry I of France (b. 1053).
November 6 – Welf I, Duke of Bavaria, duke of Bavaria.
Su Shi, Chinese statesman and poet (b. 1037)
Su Song, Chinese scientist and engineer (b. 1020)
Urraca of Zamora, Leonese princess and ruler of Zamora.
Year 1101 (MCI) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. It was the 2nd year of the 1100s decade, and the 1st year of the 12th century.