1013

By place

Europe

• King Henry II of Germany signs a peace treaty at Merseburg with Duke Bolesław I of Poland. As part of the treaty, Bolesław pays homage and recognizes Henry as his overlord in exchange for receiving the March of Lusatia and the March of Meissen as fiefs. To seal their peace, Bolesław's son Mieszko II marries Richeza of Lotharingia.
• Sulayman ibn al-Hakam reconquers the Caliphate of Córdoba in Al-Andalus and deposes Hisham II. Sulayman becomes the fifth Umayyad caliph of Córdoba.
• Winter - Henry II mobilises a German expeditionary army at Augsburg, to begin his second Italian military campaign.

  England

• Summer - Danish Viking raiders led by Sweyn Forkbeard sail from Denmark to attack England. Again London defends itself and the Vikings move elsewhere, plundering Wessex, Mercia and Northumbria. King Æthelred II sends his sons Edward and Alfred to Normandy. Æthelred retreats to the Isle of Wight and follows them later into exile.
• December 25 - Sweyn Forkbeard takes control of the Danelaw and is proclaimed king of England in London. Some of the English provinces refuse to pay homage to Sweyn, who has no dynastic right to claim the throne.

  Asia

• The Four Great Books of Song, the Song Dynasty Chinese encyclopedia Prime Tortoise of the Record Bureau, is completed in 1,000 volumes of 9.4 million written Chinese characters.
• Kaifeng, capital of China, becomes the largest city of the world, taking the lead from Córdoba in Al-Andalus.

  By topic

Medicine

• Abu al-Qasim al-Zahrawi dies. He writes Al-Tasrif, a 30-part medical encyclopedia in Arabic. Introducing his collection of over 200 surgical instruments.

  Religion

• Æthelred II appoints Lyfing as archbishop of Canterbury. He restores Canterbury Cathedral, adding porticus towers and a massive westwork.
• Beauvais changes from a county to a bishopric.