|Centuries:||11th century – 12th century – 13th century|
|Decades:||1090s 1100s 1110s – 1120s – 1130s 1140s 1150s|
|Years:||1122 1123 1124 – 1125 – 1126 1127 1128|
|1125 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Art and literature|
|1125 in poetry|
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- June 11 – Battle of Azaz: The Crusaders defeat the Seljuk Turks.
- November – Jin–Song wars: The Jurchens of the Jin Dynasty declare war on the Song Dynasty.
- May 23 – Lothair of Saxony becomes King of Germany on the death of Henry V.
- War ends between Toulouse and Provence.
- Nassau Castle is built.
- Florence conquers the neighboring independent republic of Fiesole.
- King Inge the Younger is murdered in Vreta Abbey, Östergötland, instigated by his wife Ulfhild. Her cousin Magnus the Strong proclaims himself ruler of Gothenland, whereas Ragnvald Knaphövde, in opposition to him, proclaims himself king of Sweden in Svealand.
- First mention of the consuls of Siena indicating that the city has become an independent commune.
- The Venetians pillage Rhodes, ravage Samos and Lesbos, and occupy Chios.
- Saracen pirates raid the city of Antibes in Provence and the benedictine monastery of Saint Honorat on the Lérins Islands.
- Creation of the first fair in Portugal in Ponte de Lima, it is an early sign of the commercialization and economic development of a still backward and self-contained region.
- Castellan raid in Andalusia led by king Alfonso the Battler.
- Albert of Aix begins his Historia Hierosolymitanae expeditionis.
- Reading School founded.
- October 17 (Chinese calendar) – Lu You, Chinese poet (d. 1210)
- date unknown – Renaud de Courtenay, Anglo-Norman nobleman (d. 1194)
- January 24 – King David IV of Georgia (b. 1073)
- April 12 – Vladislav I of Bohemia
- May 19 – Vladimir Monomakh, Grand Duke of Kiev
- May 23 – Henry V, Holy Roman Emperor (b. 1081)
- October 21 – Cosmas of Prague, Bohemian chronicler
- Eustace III of Boulogne
- Inge the Younger, king of Sweden since 1110
- Irnerius, teacher at Bologna
- Unité mixte de recherche 5648--Histoire et archéologie des mondes chrétiens et musulmans médiévaux. Pays d'Islam et monde latin, Xe-XIIIe siècle: textes et documents. Lyon: Presses Universitaires de Lyon.
- de Oliveira Marques, António Henrique (1998). Histoire du Portugal et de son empire colonial. Paris: Karthala. p. 44. ISBN 2-86537-844-6.
- McGrank, Lawrence (1981). "Norman crusaders and the Catalan reconquest: Robert Burdet and te principality of Tarragona 1129-55". Journal of Medieval History 7 (1): 67–82. doi:10.1016/0304-4181(81)90036-1.