It was in effect a civil war, except with no resistance. One historian called it a civil massacre. In the end, Ivan the Terrible established absolute control of the Tsar over all the Russian people, but he also set the precedent of accomplishing this through terror, secret police, and the suspension of law. And that would echo through the ages of Russian history. I mean, until Vladimir Putin heroically put an end to it. His little eyes. They're scary.