The Grand Duchy of Moscow (Russian ??????? ????????? ??????????) was a medieval Russian polity centered on Moscow between 1340 and 1547. The Grand Duchy of Moscow, as the state is known in Russian records, has been referred to by many Western sources as Muscovy. However, this term is also sometimes applied to the Tsardom of Russia. The Grand Duchy of Moscow was the successor to the Principality of Moscow and the predecessor of the Tsardom of Russia.
When the Mongols invaded the lands of Kievan Rus', Moscow was an insignificant trading outpost in the principality of Vladimir-Suzdal'. Though Mongols burnt down Moscow in the winter of 1238 and pillaged it in 1293, the outpost's remote, forested location offered some security from Mongol attack and occupation, and a number of rivers provided access to the Baltic and Black Seas and to the Caucasus region.
More important to Moscow's development into what became the state of Moscow however, was its rule by a series of princes who were ambitious, determined, and lucky. The first ruler of the principality of Moscow, Daniel I (d. 1303), was the youngest son of Alexander Nevsky of Vladimir-Suzdal. He started to expand his principality by seizing Kolomna and securing the bequest of Pereslavl-Zalessky to his family. Daniel's son George controlled the entire basin of the Moskva River and expanded westward by capturing Mozhaisk. He then forged an alliance with the overlord of the Russian principalities, Uzbeg Khan of the Golden Horde, and married his sister. He was allowed by the khan to claim the title of Grand Duke of Vladimir-Suzdal, a position which allowed him to interfere into the affairs of the Novgorod Republic to the north-west.
