1177Centuries: 11th century - 12th century - 13th century
- November 25 - Baldwin IV of Jerusalem and Raynald of Chatillon defeat Saladin at the Battle of Montgisard.
- Leopold I becomes duke of Austria.
- Manuel I Comnenus recaptures some of the former Byzantine territory lost at the Battle of Myriokephalon the previous year.
- Benedictus Abbas becomes abbot of Peterborough.
- Byland Abbey is founded in Yorkshire by the Cistercians.
- Casimir II becomes duke of Poland.
- The Cham destroy Angkor Wat.
- Sibylla of Jerusalem marries William of Montferrat.
- Roger de Moulins becomes Grand Master of the Knights Hospitaller.
- Moscow is burned down and its inhabitants are killed.
- Puigcerdą is founded by Alfonso I of Aragon.
- February 13 - Joan Plantagenet marries William II of Sicily.
- September 27 - Pope Alexander III sends a letter to Prester John, believing he is real.
- Baldwin V, king of Jerusalem
- John of Ibelin, lord of Beirut
- Philip of Swabia, rival of Otto IV, Holy Roman Emperor
- William of Montferrat, father of Baldwin V of Jerusalem
- Hugh Bigod, Earl of Norfolk