What caused the initial split between the Roman Catholic and the Greek Orthodox churches?

The Great Schism, the initial split between the Roman Catholic and the Greek Orthodox churches, came about due to a complex mix of religious disagreements and political conflicts. One of the many religious disagreements between the western (Roman) and eastern (Byzantine) branches of the church had to do with whether or not it was acceptable to use unleavened bread for the sacrament of communion.

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the key difference between a democracy and a republic lies in the limits placed on government by the law, which has implications for minority rights. both forms of government tend to use a representational system — i.e., citizens vote to elect politicians to represent their interests and form the government.