In December 1237 the army of Batu Khan opened its conquest of the Rus’ by storming the frontier city of Ryazan after a five-day assault, sacking it and massacring its people — a deliberate act of terror that set the pattern for the campaign.
The siege of Ryazan in December 1237 was the opening blow of the Mongol conquest of the Rus’. The city was stormed after five days and annihilated, a calculated massacre meant to terrify the other principalities into submission.
The Mongols who had beaten the Rus’ at the Kalka River in 1223 returned in 1237 in vast strength under Batu and Subutai. The Rus’ principalities, chronically divided, faced them one at a time. Ryazan, first in the invaders’ path, refused Batu’s demand for submission and tribute and appealed in vain to Vladimir for help.
The Mongols encircled Ryazan, cut it off with a palisade, and pounded the walls with catapults for five days. On 21 December 1237 they stormed the city. The prince, his family, and the population were massacred, the churches burned, and the town left in ruins.
Russian tradition remembers the boyar Evpaty Kolovrat, who is said to have returned to the smoking ruins, raised a small band, and harried the Mongol army in revenge — a legend expressing the shock of the catastrophe.
Ryazan’s destruction opened the road north. Within weeks Batu’s army moved on Kolomna and Moscow and then toward Vladimir, the capital of the strongest Rus’ principality, spreading the same terror as it went.