The roots were more substantial. The political leadership in Moscow took offense when their religious leaders in Kiev (Kiev was the religious capital of their brand of Orthodoxy) went to the Council of Florence and agreed to union with the Catholic Church. Corrupt secular leadership in Moscow feared accountability to anyone so they deposed the Metropolitan (a type of bishop) of Kiev and then ordered the bishops of Moscow to elect their own patriarch. That's how it got started. And the Russian Orthodox are insane. Many go so far as to say that the Catholic Church has no valid sacraments at all. They frequently get in the way of restoration of union between Rome and other Eastern Orthodox but I feel like we've hit a break point where others in the east have had enough. It is time to say "NO" to Moscow. Your political organization masquerading as a religion has done enough harm. Go to the pits of hell where you belong.