|Battle of the Pyana River|
|Part of Mongol invasion of Rus'|
The battle of the Pyana River. Illustration from the Illustrated Chronicle of Ivan the Terrible
|Dmitri Konstantinovich of Suzdal|
Boris Konstantinovich of Gorodets
The battle of the Pyana River (1367) is a battle between the troops of the Nizhny Novgorod-Suzdal Grand Duchy led by Dmitri Konstantinovich of Suzdal and Boris Konstantinovich of Gorodets against the forces of the Golden Horde led by Bulat-Timur, resulting in a decisive victory of the Russian troops.
In 1359, a long struggle for power began in the Golden Horde. The Horde suffered defeat from the Grand Duke of Lithuania Algirdas (1296-1377) in the Battle of Blue Waters in 1362 and in the Battle of the Shishev Forest from Oleg Ivanovich, Vladimir Dmitriyevich and Tit Fyodorovich in 1365 .
In 1363, Dmitri Ivanovich Donskoy established himself Aas Grand Prince of Vladimir, rejecting the claims of Dmitri Konstantinovich of Suzdal, but soon after the death of Andrei , the oldest of Konstantinoviches, in Nizhny Novgorod , sided with Dmitri Konstantinovich of Suzdal in the latter's dispute with his younger brother Boris for Nizhny Novgorod. In 1366, the union was sealed by the marriage of Dmitri Ivanovich Donskoy and Dmitri Konstantinovich's daughter Evdokia, and the following year the Horde prince Bulat-Timur raided the Principality of Gorodets (Nizhny-Novgorod).
The course of the battle
Little is known about the battle itself. The Russian army first broke the Golden Horde by the Sundovik River, and then overtook it on the Pyana River and threw it into the river. The Tartars could not retreat in an organized way and suffered heavy losses, many drowned. After returning to the Golden Horde, the rescued Bulat-Timur was killed by the Khan Aziz-Sheikh .
The victory secured the southeastern borders of the Grand Principality of Suzdal-Nizhny Novgorod for about a decade and allowed further struggle to be transferred to the middle Volga basin. The defeat of one of the Golden Horde "princes" contributed to the concentration of power in the Golden Horde in the hands of Mamai (in particular, in 1370 Dmitri Konstantinovich of Suzdal helped the governor Mamai establish himself in the middle Volga).
- Карамзин Н. М. История государства Российского