What do you see as the main reason for the dynastic crisis of 1825?

The dynastic crisis in the Russian Empire in 1825 or the interregnum occurred after the death of Emperor Alexander the First. The essence of this time was the struggle between two parties of aristocrats to put their protégé on the throne – Constantine or Nicholas. Few knew that Prince Constantine had refused the offer to take the throne in favor of his brother. Nicholas, unaware of this, also renounced his right to the throne. A situation arose when those who had taken the oath to Constantine had to swear allegiance to his brother Nicholas by the order of the first. The uprising of the Decembrists was outlined for December 26, the time of the oath of allegiance to Nicholas the First.