What are the reasons for the emergence of the state among the Eastern Slavs?

The emergence of the state among the Eastern Slavs was due to many factors. External and internal cannot be considered separately from each other, everything was closely related and interdependent.
Internal reasons include:
Separation of craft from agriculture. Trade development.
The complication of the life and life of our ancestors, the need to resolve conflicts within various social groups in society.
Allocation of the nobility, economic inequality.
The emergence of the military class.
External reasons, first of all, include:
The need for protection from attacks and raids from outside.
The influence of neighboring peoples, in particular the Vikings.
Military campaigns in foreign lands have become a profitable business.