Year 1207 (MCCVII) was a common year starting on Monday (full calendar) under the Julian calendar. Events By place Byzantine Empire Spring – Siege of Attalia: Seljuk forces led by Sultan Kaykhusraw I besiege the city port of Attalia (modern-day Antalya) with siege machines. After a siege of more than 2 months, the city is captured, Kaykhusraw allows his forces 3 days of looting and slaughtering. The capture of the port gives the Seljuk Turks a major path into the Mediterranean. September 4 – Battle of Messinopolis: Latin forces under Boniface of Montferrat are ambushed and defeated at Messinopolis. Boniface is killed and his head is sent to Kaloyan, ruler (tsar) of the Bulgarian Empire. Seeking to take advantage of the situation, Kaloyan besieges Thessalonica. In October, he dies under mysterious circumstances. Europe February 2 – Terra Mariana (or Medieval Livonia), comprising present-day Estonia and Latvia, is established as a principality of the Holy Roman Empire. During the existence of Terra Mariana, there is a constant struggle over supremacy, between the lands ruled by the Teutonic Order, the secular German nobility, and the citizens of the Hanseatic towns of Riga and Reval. Prince Mstislav Mstislavich (the Daring) clashes with his uncle Rurik Rostislavich, Grand Prince of Kiev, and is forced to surrender the town of Torchesk (a major centre of resistance against Polovtsian raids). Pope Innocent III declares for King Philip of Swabia as Holy Roman Emperor a reversal of his previous support for Philip's rival Otto IV. England King John (Lackland) introduces the first income tax. One-thirteenth of income from rents, and moveable property has to be paid. Collected locally by sheriffs and administered by the Exchequer. The tax is unpopular with the English nobility and especially in the churches and monasteries. The tax does raise a lot of money for John, doubling his annual income for the year. May 24 – John (Lackland) still refuss to accept Stephen Langton as archbishop, Innocent III threatens to place England under an Interdict. In response, John confiscates church property. Many of the English bishops of the great churches in the country flee abroad to the Continent. November – Leeds, a market town in West Yorkshire, receives its first charter (approximate date). Asia Jochi, eldest son of Genghis Khan, subjugates people of the Siberian forest (taiga); the Uriankhai, the Oirats, the Barga, the Khakas, the Buryats, and the Tuvans. Extending the northern