|Centuries:||11th century · 12th century · 13th century|
|Decades:||1090s · 1100s · 1110s · 1120s · 1130s · 1140s · 1150s|
|Years:||1120 · 1121 · 1122 · 1123 · 1124 · 1125 · 1126|
|1123 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Art and literature|
|1123 in poetry|
|Ab urbe condita||1876|
|English Regnal year||23 Hen. 1 – 24 Hen. 1|
|Chinese calendar||壬寅年 (Water Tiger)|
3819 or 3759
— to —
癸卯年 (Water Rabbit)
3820 or 3760
|- Vikram Samvat||1179–1180|
|- Shaka Samvat||1044–1045|
|- Kali Yuga||4223–4224|
|Japanese calendar||Hōan 4|
|Minguo calendar||789 before ROC|
|Seleucid era||1434/1435 AG|
|Thai solar calendar||1665–1666|
|Wikimedia Commons has media related to 1123.|
- August 9 – Failure of a Norman campaign in North Africa, the Norman troops are massacred near Mahdia at the battle of al-Dimas.
- February 25 – 5-year-old Emperor Sutoku succeeds his father Emperor Toba on the throne of Japan when the latter is forced to abdicate at the age of 21.
- May 29 – Battle of Yibneh: A Crusader force led by Eustace Grenier crushes a Fatimid army at Yibna.
- May 30 – The Venetian fleet defeats the Egyptian fleet off Ascalon.
- The Pactum Warmundi is established between the Republic of Venice and the Kingdom of Jerusalem.
- First mention of the consuls of Bologna indicating that the city has become an independent comune of Italy.
- Siege of Deventer: Conflict between Henry V, Holy Roman Emperor and Lothair of Supplinburg, Duke of Saxony.
- In accordance with the decision of the First Council of the Lateran, the archbishop of Compostela, Diego Gelmírez, declares the Crusade in Iberia against the Andalusians.
- March 18 – First Council of the Lateran convenes in Rome; it confirms the Concordat of Worms (1122) and demands clerical celibacy in the Catholic Church.
- St Bartholomew's Hospital ("Barts") is founded in London; it will still be operating as a medical institution on its original site into the 21st century.
- Furness Abbey founded in the north-west of England by Stephen, Count of Boulogne, for the Order of Savigny; it will become the country's second wealthiest and most powerful Cistercian monastery.
- August 29 – King Eystein I of Norway (b. c. 1088)
- Emperor Taizu of Jin, chieftain of the Jurchen Wanyan tribe (b. 1068)
- Saint Peter of Pappacarbone
- Meynier, Gilbert (2010). L'Algérie cœur du Maghreb classique: De l'ouverture islamo-arabe au repli (658-1518). Paris: La Découverte. p. 56.
- Johns, Jeremy (2002). Arabic administration in Norman Sicily: the royal dīwān. Cambridge University Press. p. 85. ISBN 0-521-81692-0.
- "Venice - Adriatic Powerhouse". Pericles Press. 2013. Retrieved 2014-02-03.
- Fletcher, R. A. (1987). "Reconquest and Crusade in Spain c. 1050-1150". Transactions of the Royal Historical Society. 5. 37: 31–47 . JSTOR 3679149.