On this day, 675 years ago, October 12, 1350 (September 11, 1350, the lunar calendar), the famous Russian Archduke Donskoy was born. Dmitry Ivanovic (October 12, 1350-May 19, 1389) is better known as Dmitry Donskoy (meaning Dmitry of the Don River), Grand Duke of Moscow, reigned from 1359 to 1389. During the reign of Dmitry Ivanovic, the wooden walls around the city of Moscow were converted into stone walls to defend against foreign invasion. At the same time, the Grand Duchy of Moscow continued to fight against neighboring duchies, forcing them to submit to itself. The war severely weakened the power of the Duchy of Tver. As the Duchy of Moscow gradually became stronger, the Golden Horde Khanate gradually became weaker. In 1378, Mamehan, the Golden Horde Khanate, sent Tatar princes to join forces with the Dukes of Lithuania and Ryazan to attack Moscow. Dimitri led 150,000 troops to meet it. In 1380, Dmitry led his troops to a decisive battle with the Mongolian Tatar army in the Kurikowo Field in the Don River Valley, and defeated the troops of the Golden Horde Khanate. The battle broke the myth of the invincible Mongolian army, and Dmitry was honored as "Donskoy"(meaning "Don Hero"), and the Grand Duchy of Moscow achieved temporary independence. But soon in 1383, the independence of the Grand Duchy of Moscow was cancelled by Tuotuo Lost's invasion. Comments: Made immortal contributions to the reunification of Russia