Year 1217 (MCCXVII) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar.
Mukhali is back in Genghis Khan's camp in Mongolia and receives the hereditary title of prince, a golden seal, and a white standard with 9 tails and a black crescent in the middle. He is appointed commander in chief of operations in North China.
The Fifth Crusade reaches the Holy Land
April 9 – Peter II of Courtenay is crowned emperor of the Latin Empire of Constantinople at Rome, by Pope Honorius III.
May 20 – First Barons' War in England: Occupying French forces are defeated at the Battle of Lincoln by English royal troops led by William Marshal, Earl of Pembroke and survivors forced to flee south.
June 6 – King Henry I of Castile dies aged thirteen from the fall of a roof tile in Palencia, an event which his regent, Álvaro Núñez de Lara, attempts to conceal. Henry's sister Berengaria succeeds to the throne.
June – Haakon Haakonsson becomes King Haakon IV of Norway following the death of Inge II and largely ends the civil war era in Norway, reigning until 1263.
August 24 – First Barons' War: In the Battle of Sandwich in the English Channel, English forces destroy the French and the French mercenary Eustace the Monk is captured and beheaded.
August 31 – Ferdinand becomes King of Castile on abdication of his mother Berengaria.
September 12 – First Barons' War in England ended by the Treaty of Kingston upon Thames: French and Scots are to leave England, and an amnesty is granted to rebels.
September 20 – Treaty of Lambeth signed ratifying the Treaty of Kingston.
September 21 – Livonian Crusade: The Livonian Brothers of the Sword and allied Livs and Letts defeat the Estonian army in the Battle of St. Matthew's Day and kill their leader Lembitu.
October 18 – Fifth Crusade, Reconquista: Alcácer do Sal is reconquered by the troops of King Afonso II of Portugal.
November – In the Kingdom of Castile, former regent Álvaro Núñez de Lara is captured and forced to relinquish all his castles.
Stefan Nemanjić is elevated to be first King of the Serbian lands by Pope Honorius III and crowned by Stefan's brother, Archimandrite Sava, in Žiča.
A decree made in England establishes that only Englishman can be clergy of Ireland.
John I, Duke of Brittany (d. 1286)
Baldwin, Latin Emperor of Constantinople (d. 1273)
Henry I of Cyprus
Eleanor of Provence, Queen of Henry III of England (d. 1291)
Hulagu Khan, Mongol ruler of Persia (d. 1265)
Boniface of Savoy, Archbishop of Canterbury (d. 1270)
Izz al-Din ibn Shaddad, Arab historian (d. 1285)
April 23 – King Inge II of Norway (b. 1185)
April 25 – Hermann I, Landgrave of Thuringia
June 6 – King Henry I of Castile (b. 1204)
August 24 – Eustace the Monk, French mercenary and pirate (b. c.1170)
September 10 – William de Redvers, 5th Earl of Devon, English nobleman
September 21 – Lembitu of Lehola, Estonian resistance leader and Caupo of Turaida, Livonian leader (at the Battle of St. Matthew's Day)
October 14 – Isabella, Countess of Gloucester, wife of King John of England (b. c.1173)
Maria Comnena, wife of Amalric I of Jerusalem (b. c.1154) (latest possible date of death)
Lovers of Teruel: Juan Martinez (aka Diego Marcilla) and Isabel Segura (alleged date)
1217 Wikipedia (Text) CC BY-SA