What were the features of the history of the Chernigov and Smolensk principalities in the 12th – early 13th centuries?

Chernigov and Smolensk principalities in the 12-13th centuries were the first to detach from a single state. They gravitated towards independence like the Novgorod and Polotsk principalities. They strove for independence from the Kiev principality, because they had the opportunity to improve the economy on their own. The principalities traded with Western states and exchanged cultural traditions. They independently developed many crafts and economic activities. During the feudal fragmentation, they strengthened.