Browse Historical Events by Month: What Happened in April?

William the Conqueror, Duke of Normandy, becomes the Duke at the age of 8 after the death of his father, Robert I.

Nizam al-Mulk, Persian scholar and vizier of the Seljuk Empire, is born.

Pope Damasus II is consecrated as the 151st pope.

Persian mathematician, astronomer, and poet Omar Khayyam is born.

Pope Leo IX issues a papal bull excommunicating the Patriarch of Constantinople, Michael I Cerularius, sparking the Great Schism between the Eastern and Western Christian Churches.

Pope Victor II succeeds Leo IX as the 153rd pope. Born Gebhard of Dollnstein-Hirschberg, c. 1018. He was one of a series German-born Popes who led the Gregorian Reform. He died in 1057. More 

Pope Stephen IX (X) becomes the 154th pope.

Pope Nicholas II succeeds Pope Stephen IX as the 155th pope.

Halley's Comet makes its closest known approach to Earth, a significant event before the Battle of Hastings.

Seljuk Turks capture Baghdad, leading to the decline of the Abbasid Caliphate.

Battle of Manzikert: The Seljuk Turks defeat the Byzantine Empire, leading to Turkish dominance in Anatolia.

Pope Alexander II dies after a papacy that advanced many reforms in the Catholic Church.

The Synod of Worms condemns Pope Gregory VII and excommunicates Henry IV, Holy Roman Emperor.

Henry IV, Holy Roman Emperor, submits to Pope Gregory VII at Canossa, seeking absolution.

Pope Gregory VII excommunicates Henry IV for a second time.

Alexios I Komnenos becomes Byzantine emperor after the death of Nikephoros III Botaneiates.

Alfonso VI of Castile and León captures Toledo, Spain, from the Moors.

William the Conqueror, King of England, dies in Rouen, France.

The Battle of Levounion: The Byzantine Empire defeats the Pechenegs.

Malcolm III of Scotland, husband of Saint Margaret of Scotland, dies in battle against the English.