1084

By place

Europe

• March 31 - Emperor Henry IV besieges Rome and enters the city. He is crowned emperor by Antipope Clement III at Rome and receives the patrician authority.
• May - Sack of Rome: Duke Robert Guiscard leads an Norman army north and enters Rome, the city is sacked and Henry IV is forced to retreat.
• Robert Guiscard returns with 150 warships in Illyria, and occupies Corfu and Kefalonia with the support of Ragusa and the Dalmatian cities.
• King Halsten Stenkilsson is killed and his brother Inge the Elder is deposed in Svealand. Inge is replaced by his brother-in-law Blot-Sweyn.

  Seljuk Empire

• The Seljuk Turks under Sultan Malik-Shah I conquer Byzantine Antioch, held by Philaretos Brachamios, an Armenian general, who seize power as a usurper.

  Asia

• Sima Guang, Chinese chancellor and historian, completes with a group of scholars the Zizhi Tongjian, an chronicle of the universal history of China.
• April 21 - King Kyansittha begins his reign as ruler of the Pagan Kingdom in Burma.

  By topic

Religion

• Pope Gregory VII, who is imprisoned by Henry IV in Castel Sant'Angelo, is freed by Robert Guiscard. He restores papal authority in Rome.
• Bruno of Cologne founds the Carthusian Order which includes both monks and nuns. He builts an hermitage in the French Alps.
• Building work starts on Worcester Cathedral. Orchestrated by Bishop Wulfstan.