Year 1177 (MCLXXVII) was a common year starting on Saturday of the Julian calendar.
Events
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January–December
- January – Eystein Meyla, leader of the Birkebeiner in Norway, is killed. Sverre Sigurdson (Later, King Sverre I, of Norway) becomes the new leader.
- January 13 – Leopold V becomes Duke of Austria.
- March – Treaty of Venice: Frederick I Barbarossa acknowledges Alexander III as Pope, after a diplomatic mediation by Venetian doge Sebastiano Ziani.
- March 16 – The Spanish Award is signed and witnessed by, among others, Robert III de Stuteville and John of Greenford
- August 1 – The Holy Roman Empire renounces any claims on the territory of Rome.
- September 27 – Pope Alexander III sends a letter to Prester John, believing he is real.
- November 25 – Battle of Montgisard: Baldwin IV of Jerusalem and Raynald of Chatillon defeat Saladin.
Date unknown
- During the third year of the Angen era in Japan, a fire devastates Kyoto.
- During the winter, the Estonians attack Pskov.
- Casimir II overthrows his brother Mieszko III the Old, to become High Duke of Poland.
- The Cham sack the Khmer capital of Angkor. The date is disputed.
- Moscow is burned down by Gleb I, prince of Ryazan, and its inhabitants are killed.
- A civil war breaks out in the Republic of Florence, between the Uberti Family and their consular opponent.
- Puigcerdà is founded by Alfonso II of Aragon.
- Byland Abbey is established on its final site in Yorkshire, England, by the Cistercians.
- Abbas Benedictus becomes abbot of Peterborough in England.
- Roger de Moulins becomes Grand Master of the Knights Hospitaller.
- possible date – Richard FitzNeal begins to write his treatise Dialogus de Scaccario ("Dialogue concerning the Exchequer") in England.</onlyinclude>
- The union of Egypt and Syria under Sultan Saladin Yusuf ibn Ayyub, the foundation of the Ayyubid Sultanate.
Births
- February/March – Philip of Swabia, rival of Otto IV, Holy Roman Emperor (d. 1208)
- August – Baldwin V, King of Jerusalem (d. 1186)
- Marie of Oignies, French beguin (d. 1213)
- Prithviraj Chauhan, Indian ruler of Ajmer (d. 1192)
- Sylvester Gozzolini, Italian founder of the Sylvestrines (d. 1267)
Deaths
- January 13 – Henry II, Duke of Austria (b. 1107)
- January – Eystein Meyla, leader of the Birkebeiner in Norway. (b. 1157)
- probable – Hugh Bigod, 1st Earl of Norfolk (b. 1095)
