|Ab urbe condita||1862|
|Balinese saka calendar||1030–1031|
|English Regnal year||9 Hen. 1 – 10 Hen. 1|
|Chinese calendar||戊子年 (Earth Rat)|
3805 or 3745
— to —
己丑年 (Earth Ox)
3806 or 3746
|- Vikram Samvat||1165–1166|
|- Shaka Samvat||1030–1031|
|- Kali Yuga||4209–4210|
|Japanese calendar||Tennin 2|
|Minguo calendar||803 before ROC|
|Seleucid era||1420/1421 AG|
|Thai solar calendar||1651–1652|
1235 or 854 or 82
— to —
1236 or 855 or 83
|Wikimedia Commons has media related to 1109.|
- July 12 – Siege of Tripoli: After a 7-year siege (supported by the Genoese fleet), Tripoli falls to the Crusaders. Fakhr al-Mulk Radwan, Seljuk sultan of Aleppo, submits to Bertrand of Toulouse (the eldest son of Raymond IV). He establishes the County of Tripoli, the fourth Crusader state in the Middle East. Bertrand deposes Raymond's nephew William II (Jordan) as nominal count of Tripoli, who dies of an arrow wound sustained during the siege.
- Summer – Almoravid emir Ali ibn Yusuf organizes an public ritual of penance (auto-da-fé) of the works of Al-Ghazali, in front of the Great Mosque of Cordoba.
- July 1 – Urraca of León becomes queen of León, Castile and Galicia after the death of her father, King Alfonso VI (the Brave). She marries Alfonso I (the Battler).
- August 10 – Battle of Nakło: Bolesław III (Wrymouth) leads an expedition into Pomerania. He besieges the castle of Nakło, and defeats a Pomeranian relief force.
- August 24 – Siege of Głogów: German forces led by King Henry V besiege Głogów. He is forced to abandon the siege – due to attacks of Polish guerilla warriors.
- August 24 – Battle of Hundsfeld: Bolesław III defeats the imperial forces under Henry V at Hundsfeld (Silesia). The Germans are ambushed by the Polish forces.
- The Almoravid army led by Ali ibn Yusuf fails to reconquer Toledo (lost in 1085).
- July 25 – Afonso I (the Conqueror), king of Portugal (d. 1185)
- September 7 – Gongye, Korean queen (d. 1183)
- October 29 – Injong of Goryeo, Korean king (d. 1146)
- Abu'l-Hasan al-Hasan ibn Ali, Zirid emir (d. 1171)
- Al-Rashid, caliph of the Abbasid Caliphate (d. 1138)
- Béla II (the Blind), king of Hungary and Croatia (d. 1141)
- Bertrand de Blanchefort, French Grand Master (d. 1169)
- William d'Aubigny, 1st Earl of Arundel (d. 1176)
- January 26 – Alberic of Cîteaux, French abbot
- April 14 – Fulk IV (the Quarreler), count of Anjou (b. 1043)
- April 21 – Anselm, archbishop of Canterbury (b. 1033)
- April 28 – Hugh the Great, abbot of Cluny (b. 1024)
- May 12 – Dominic de la Calzada, Spanish priest (b. 1019)
- July 1 – Alfonso VI (the Brave), king of León and Castile
- September 21 – Svatopluk (the Lion), duke of Bohemia
- November 16 – Ingulf, Norman Benedictine abbot
- Eupraxia of Kiev (Praxedis), Holy Roman Empress
- Ngok Loden Sherab, Tibetan Buddhist monk (b. 1059)
- William II (Jordan), count of Cerdagne and Tripoli
- Gilbert Meynier (2010). L'Algérie cœur du Maghreb classique. De l'ouverture islamo-arabe au repli (658-1518). Paris: La Découverte; p. 86.
- Gilbert Meynier (2010). L'Algérie cœur du Maghreb classique. De l'ouverture islamo-arabe au repli (658-1518). Paris: La Découverte; p. 84.