The defeat at the Kalka River had left the Kievan principality at the mercy of invaders, but the Mongol forces had retreated, not to reappear for thirteen years, during which time the princes of Rus' have gone on quarreling and fighting as before, until they are startled by a new and much more formidable invading force.

The main Mongol force, headed by Jochi's sons, and their cousins, Möngke Khan and Güyük Khan, arrive at Ryazan in December 1237.

Ryazan refuses to surrender, and the Mongols sack it.

The Principality is completely overrun with almost the whole princely family killed and the capital completely destroyed; it will later be moved to another location.

After Tokhtamysh's initial defeat, Timur invades Muscovy to the north of Tokhtamysh's holdings.

Timur's army burns Ryazan and advances on Moscow.

He is pulled away before reaching the Oka River by Tokhtamysh's renewed campaign in the south.

Grand Prince Vasili III of Russia had captured and imprisoned in Moscow the Grand Prince of Ryazan, Ivan V, because of his relations with the Crimean Khan Mehmed I Giray.

In 1521, Prince Ivan flees into the Grand Duchy of Lithuania.

After this, in 1521, the Ryazan Principality is merged with Muscovy.

The Polish forces outside Moscow under the command of Jan Piotr Sapieha clash with the growing anti-Polish Russian forces of the so called First Volunteer Army, led by Prokopy Petrovich Lyapunov.

Prokopy and his brother Zakhary, Russians of Rurikid stock, had sided with False Dmitriy I after the death of Boris Godunov.

Prokopy in early 1606, had taken part in the Bolotnikov Uprising on the side of the rebels.

Lyapunov had come to Moscow in November of 1606 and given himself up to Vasili IV.

After his repentance, Lyapunov had been made a dvoryanin (noble) of the Boyar Duma (1607).

Lyapunov had in 1608–1610 led the army of service class people against a peasant uprising in the Ryazan region and supporters of False Dmitriy II.

Lyapunov had been the one to organize the overthrowing of Vasili IV in July of 1610.

When the Polish army occupied Moscow, Lyapunov, inspired by Patriarch Germogen's proclamations, had levied the so-called First People's Volunteer Army and become its leader.

The People's Volunteer Army approaches Moscow in March of 1611 and blocks the Polish invaders.

Lyapunov has by the summer of 1611 practically become the head of the interim government.

He issues a decree on June 30 that reinstates certain serf regulations and violates his own promises to Cossacks of "freedom and salary".

The indignant Cossacks kill Lyapunov on August 1, 1611 (O.S.).