Their influence upon the young tsar was profoundly beneficial, and the period of their administration coincides with the most glorious period of Ivan's reign - the period of the conquest of Kazan and Astrakhan.
Some of Ivan's advisers, including both Sylvester and Adashev, now advised him to make an end of the Crimean khanate, as he had already made an end of the khanates of Kazan and Astrakhan.
Even went so far as to disperse 123 skilled Germans whom Ivan's agent had collected and brought to Lubeck for shipment to a Baltic port.
Ivan's generals (he himself rarely took the field) were generally successful at first, and bore down their enemies by sheer numbers, capturing scores of fortresses and towns.
From that moment Ivan's subjects noticed a change in his attitude towards them, and attributed it to the evil influence of the Greek princess.
During Ivan's minority the country was governed, or rather misgoverned, first by his mother, and then by rival factions led by great nobles such as the princes Shuiski and Belski.
After a short campaign a peace was concluded and Ivan's daughter was given in marriage to the Lithuanian grandprince, but the matrimonial alliance did not improve the relations between the two countries.
In the instructions sent to Ivan's guardian, Prince Churmtyev, the latter was ordered to chain up his charge, and even scourge him should he become refractory.
By this time, twenty years of solitary confinement had disturbed Ivan's mental equilibrium, though he does not seem to have been actually insane.
In 1571 he strengthened his position at court by his marriage with Maria, the daughter of Ivan's abominable favourite Malyuta Skuratov.
The reign of Theodore began with a rebellion in favour of the infant tsarevich Demetrius, the son of Ivan's fifth wife Marie Nagaya, a rebellion resulting in the banishment of Demetrius, with his mother and her relations, to their appanage at Uglich.
On the 23rd of May, however, the Naruishkin faction was overthrown by the stryeltsi (musketeers), secretly worked upon by Ivan's half-sister Sophia, and Ivan was associated as tsar with Peter.