|Centuries:||11th century – 12th century – 13th century|
|Decades:||1140s 1150s 1160s – 1170s – 1180s 1190s 1200s|
|Years:||1170 1171 1172 – 1173 – 1174 1175 1176|
|1173 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Art and literature|
|1173 in poetry|
|Ab urbe condita||1926|
|English Regnal year||19 Hen. 2 – 20 Hen. 2|
— to —癸巳年十一月廿五日
|- Vikram Samvat||1229–1230|
|- Shaka Samvat||1095–1096|
|- Kali Yuga||4274–4275|
|- Ǹrí Ìgbò||173–174|
|Juche calendar||N/A (before 1912)|
|Julian calendar||1173 MCLXXIII|
|Minguo calendar||739 before ROC
|Thai solar calendar||1716|
|Wikimedia Commons has media related to: 1173|
By area 
- End of Qiandao era and start of Chunxi era of the Chinese emperor Xiaozong.
- Saladin seizes Aden in Arabia.
- March - Henry the Young King withdraws to the French court, marking the beginning of the Revolt of 1173–1174, in which Eleanor of Aquitaine and her sons rebel against her husband Henry II of England.
- Abergavenny Castle is seized by the Welsh.
- Upon the death of Kol Sverkerson, king Knut Eriksson extends his reign to also include Östergötland. He is now unopposed as king of Sweden.
- Casimir II of Poland succeeds Boleslaus IV of Poland on the throne.
- The efforts of the Almohad caliph, Abu Yaqub Yusuf, to repopulate the western Andalusian city of Beja begin. They are rapidly abandoned, sign of the quick demographic weakening of the Muslim in the peninsula.
By topic 
Arts and leisure 
- August 8 – The construction of a campanile which will become the Leaning Tower of Pisa begins.
- Algebraic chess notation is first recorded.
- Saint Thomas Becket is buried at Canterbury and canonized.
- Peter Waldo is converted to Christianity and founds the Waldensians.
- Llywelyn the Great, Prince of Aberffraw and Lord of Eryri (approximate date; d. 1240)
- Rostislav II of Kiev (d. 1214)
- Shinran, Japanese founder of Jodo Shinshu Buddhism (d. 1263)
- Conrad II, Duke of Swabia (d. 1196)
- Tankei, Japanese sculptor (d. 1256)
- April 3 – Bolesław IV the Curly, High-Duke of Poland (b. 1120)
- August 9 – Najm ad-Din Ayyub, father of Saladin
- Roger de Clare, 3rd Earl of Hertford (b. 1116)
- Vladimir II Mstislavich, Grand Prince of Kiev (b. 1132)
- Richard of St. Victor, French mystic and theologian
- Benoît de Sainte-Maure, French poet and troubadour (b. 1154)
- Kol Sverkerson, king of Östergötland (Sweden) since 1167