Events on September 3
| Date | Type | Event |
|---|---|---|
| 3 September 863 | Battles & Sieges | (3 September) During the Battle of Lalakaon, Byzantine forces defeated an Arab raiding army, resulting in the death of Emir Umar al-Aqta of Malatya (Melitene). |
| 3 September 1260 | Battles & Sieges | (3 September) The forces of the Mamluks of Egypt defeated the Ilkhanid armies of Hulagu Khan under Kitbuga at the Battle of Ain Jalut. |