Eastern Orthodox Catholics and Roman Catholics exist today because of what is known as the Great East-West Schism of 1054, when Christianity split into two branches. The basic issue was whether the Bishop of Rome or the Patriarch of Constantinople should be the head of the Christian Church. The emperor was a member of the bishop's congregation, so many accepted that he was the most important bishop. So when the emperor moved to Constantinople and became a member of the Patriarch's congregation, the Patriarch claimed his was the chief bishop. And the battle began.

The conflict reached its head in the beginning of the 11th century. The majority of Christians believed that Jesus would return in the year 1000. And he would resolve any conflict. When he didn't return, the Bishop and the Patriarch resolved the matter on their own. They excommunicated each other and all the members of the opposing church. The entire history of the world was changed at this point.

This was one of the greatest schisms in history, but not the only one.  Religious schisms have continued ever since. Martin Luthor and the Pope. The Puritans and the Church of England. 

In the metaphysical community we have more than our share of schisms.  The most recent is the schism from Pagan Pride.  What is at the basis of these schisms?

Ego. Someone feels that things should be done their way. Others do not agree - BIngo - schism.

Power. Someone wants to be in charge. They accumulate a clique  And then there is a schism.

Hurt feelings. Someone's feelings were hurt because there was a misunderstanding or they felt left out. They quit and sometimes others went with them.

Usually, the two groups remain mad at each and never cooperate on anything.

Very seldom (if ever) is it about tenets or policies.

Can't we all just get along?