Year 1238 (MCCXXXVIII) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. Events By place Mongol Empire January 15–20 – Siege of Moscow: The Mongols under Batu Khan and Subutai campaign across the northern heartland of the Kievan Rus', committing numerous atrocities across multiple settlements, including the sacking of an irrelevant little town known as Moscow. According to the Chronicle of Novgorod, Moscow is a fortified village, a trading post "on a crossroads of four rivers". The village is taken by the Mongols after 5 days of siege. March 4 – Battle of the Sit River: The Mongols defeat a Kievan Rus' army (some 4,000 men) under Grand Prince Yuri II of Vladimir in an engagement at the Sit River (located in the Sonkovsky District). With Yuri's death, so too dies the hope of any united Rus' resistance against the Mongols. Batu Khan splits his forces up into several contingents – ordering each to wreak havoc across the Rus' territories (modern-day Russia and Ukraine). March – Siege of Kozelsk: The 12-year-old Prince Vasily of Chernigov (grandson of Mstislav II Svyatoslavich), manages against all the odds, to hold out in his capital of Kozelsk for nearly two months with only citizen militia. He leads a successful sortie outside of the walls – where the garrison slaughters thousands of Mongols and destroys siege equipment. Finally, Kozelsk is conquered and Vasily is slaughtered alongside the inhabitants. Evpaty Kolovrat, Kievan knight (bogatyr), returns to his hometown of Ryazan, which is burnt to the ground by the Mongols (see 1237). He gathers some 1,700 survivors and pursues Batu Khan, attacking his rearguard, and annihilating thousands of Mongols. Finally, Kolovrat is slain from afar by siege-weaponry. Batu Khan shows admiration for his bravery and as a sign of respect, returns his body and allows his soldiers to return home. Autumn – The Mongols under Batu Khan retire, leaving behind the ruined northern Rus' territories. He spends the rest of the year suppressing the last resistance of the Kipchaks, while his cousin Möngke (son of Tolui Khan) conquer the Alans and the northern Caucasian tribes. Later, Möngke makes a raid of reconnaissance as far as Kiev. Europe June 8 – Treaty of Stensby: The Teutonic Knights sign a agreement with King Valdemar II (the Conqueror). William of Modena, Italian papal diplomat, meets Grand Master Hermann Balk and Valdemar on