1173

Year 1173 (MCLXXIII) was a common year starting on Monday of the Julian calendar.

• Mieszko III (the Old), and as duke of Sandomierz in Lesser Poland by Casimir II
  (the Just).
• King
  Canute I (Knut Eriksson) extends his rule after the death of co-ruler Kol – which includes also Östergötland. He becomes the unopposed sole-ruler of Sweden. Canute is supported by Earl Birger Brosa
  .
• Beja. But it is rapidly abandoned, a sign of the quick demographic weakening of the Muslims in the peninsula.^[1]

• Spring –
  Revolt of 1173–74, in which former Queen Eleanor of Aquitaine and her sons rebel against her ex-husband King Henry II
  .
• Richard de Luci (or Lucy).^[2]

• Summer –
  Oultrejordain to secure a route between Egypt and Syria. He raids the region at Kerak Castle.^[3]
• Pro-Fatimid rising in Upper Egypt led by Kanz al-Dawla, governor of Aswan, is crushed by Saladin's brother Al-Adil.

• The Qiandao era ends and the Chunxi era begins during the reign of Emperor Xiao Zong of the Song dynasty.

South India

• Sinhalese king Parakramabahu the Great gains a decisive victory by invading the Chola Empire as an ally of the Pandyas, capturing Tondi and Pasi regions.

• August 8 – The construction of a campanile, which will become the Leaning Tower of Pisa, begins.
• Algebraic chess notation
  is first recorded.

• King Béla III invites Cistercian and Premonstratensian monks to Hungary. They introduce advanced agricultural methods in the realm (approximate date).

• February 21 – Thomas Becket is canonized by Pope Alexander III. His tomb in Canterbury Cathedral becomes a shrine and a popular pilgrimage destination.^[4]
• Peter Waldo, French spiritual leader, is converted to Christianity and founds the Waldensians.
• The
  Great Mosque of al-Nuri in Mosul
  is completed (approximate date).

• archdiocese of Santiago de Compostela after some controversy.^[5]

• May 21 – Shinran, founder of Shin Buddhism (d. 1263)
• October 31 – Kujō Ninshi, Japanese empress (d. 1239)
• December 23 – Louis I, duke of Bavaria (d. 1231)
• Diya al-Din al-Maqdisi, Arab Sunni scholar (d. 1245
  )
• Berg-Altena
  (approximate date)
• Isabella, countess of Gloucester (approximate date)
• Kamal al-Din Isfahani, Persian poet and writer (d. 1237)
• Kolbeinn Tumason, Icelandic chieftain (d. 1208)
• Llywelyn the Great, king of Gwynedd (d. 1240
  )
• Louis IV (the Young), French nobleman (d. 1226)
• Rostislav II, Grand Prince of Kiev (d. 1214)
• Buddhist sculptor (d. 1256
  )
• Walter Devereux, Norman nobleman (d. 1197)

• Poland
• February 10 – Muiredach Ua Cobthaig, Irish bishop
• March 10 – Richard of Saint Victor, Scottish theologian
• May 25 – Euphrosyne of Polotsk, Belarusian granddaughter
• Najm ad-Din Ayyub, father of Saladin
• August 13 – Nerses IV, Catholicos of Armenia (b. 1102)
• October 15 – Petronilla, queen of Aragon (b. 1136)
• November 7 – Uijong, Korean ruler Goryeo (b. 1127)
• Benjamin of Tudela, Spanish Jewish traveler (b. 1130)
• Benoît de Sainte-Maure, French poet and writer
• Fujiwara no Ikushi, Japanese empress (b. 1146)
• Hemachandra, Indian poet and polymath (b. 1088)
• Kol of Sweden, Swedish ruler of Östergötland
• Hoysala Empire
• Raimbaut d'Aurenga, French troubadour (b. 1147)
• Rajaraja II, Indian ruler of the Chola dynasty
• Reginald Fitzurse, English nobleman (b. 1145)
• Earl of Hertford (b. 1116
  )
• Vladimir III, Grand Prince of Kiev (b. 1132
  )