|Centuries:||10th century – 11th century – 12th century|
|Decades:||980s 990s 1000s – 1010s – 1020s 1030s 1040s|
|Years:||1015 1016 1017 – 1018 – 1019 1020 1021|
- The Liao Dynasty invades Goryeo.
- Largest amphibious invasion force in history at the time. Chola army that invaded Lanka (Sri Lanka) with a massive manpower of 150,000 troops.
- Battle of Kwiju: Korean General Gang Gam-chan gains a victory over Liao Dynasty forces during the Third Goryeo-Khitan War.
- January 30 – The Peace of Bautzen is signed between Poland and Germany.
- July 22–23 – Bolesław I Chrobry, Duke of Poland, defeats Yaroslav the Wise in the Battle of the River Bug. Yaroslav retreats to Novogrod, abandoning Kiev.
- July 29 – Dirk III, Count of Holland, defeats an army sent by Henry II, Holy Roman Emperor, in the Battle of Vlaardingen.
- August – Leader of the remaining Bulgarian resistance, Ivats, is blinded and captured by strategos Eustathios Daphnomeles, confirming Bulgaria's position as part of the Byzantine Empire.
- August 14 – Bolesław accepts the surrender of Kiev by the Pechenegs. He reinstates Sviatopolk as Grand Prince of Kiev.
- c. October? – In Southern Italy, at the second battle of Cannae, the Lombard adventurer Melus of Bari and his Norman mercenaries are defeated by the Byzantine army led by the Catepan Basil Boioannes.
- Probable date