Ivan finally agrees to return to Moscow on two conditions.
Firstly, he is to be granted a political and territorial subdivision, the “Oprichnina,” managed entirely at his discretion.
Secondly, he is to have the right to punish traitors and transgressors, executing them when necessary and confiscating their holdings.
The “oprichnina” includes most of Russia’s wealthy towns, cultivated areas and trade routes, the natural stronghold of the wealthy old boyar families.
Moscow’s metropolitan, fearing a large popular revolt in the tsar’s favor, agrees not to interfere with Ivan’s vendetta and his establishment of the Oprichnina, an extensive domain directly controlled by the tsar and policed by his personal servicemen, a corps of enforcers called the Oprichniki, who Ivan uses to kill, imprison, or banish many of the boyars and their families, then appropriates their lands.
The Oprichnina, who reportedly dress all in black and ride black horses in order to inspire terror, bear the insignia of a dog's head and a broom.
The dog symbolizes their loyalty to the tsar (Oprichniks are sometimes called "Tsar's Dogs", both the name and the symbol allusions, likely deliberate, to Dominicans, "dogs of the Lord"), and the broom means that his enemies will be swept away.
