Peter changes the rules of succession to…

Peter changes the rules of succession to the throne after he kills his own son, Aleksey, who had opposed his father's reforms and served as a rallying figure for anti-reform groups.

A new law provides that the tsar will choose his own successor, but Peter fails to do so before his death in 1725.

In the decades that follow, the absence of clear rules of succession leave the monarchy open to intrigues, plots, coups, and counter-coups.

Henceforth, the crucial factor for obtaining the throne is the support of the elite palace guard in St. Petersburg.