1123

Events 
 First Council of the Lateran confirms Concordat of Worms and demands that priests remain celibate.
 End of the reign of Emperor Toba, emperor of Japan.
 Emperor Sutoku ascends to the throne of Japan.
 St Bartholomew's Hospital (Barts) founded in London, England.
 The Pactum Warmundi is established between the Republic of Venice and the Kingdom of Jerusalem.

 Births 
 Minamoto no Yoshitomo, Japanese general (d. 1160)
 Leonardo Fibonacci, Mathematician born (d. 1209)

 Deaths 
 August 29 — Eystein I of Norway (b. around 1088)
 Wanyan Aguda, chieftain of the Jurchen Wanyan tribe (b. 1068)
 Peter of Pappacarbone