Hereditary monarchies

Although the differences between the two parties appeared to rest on the problem of the rightful heir to the office of caliph, the animosities were much deeper and involved basic differences in racial background and ancient traditions. Racially, the Shiites were mainly Persians of Aryan ancestry. It was their custom, based on a tradition that reached back to the time of the great Persian empire, to be governed by a hereditary monarchy. The Sunnis, who represented the majority of Arabs, were Semitic in origin. Their custom was to elect leaders on the basis of personal merit., not blood line. 

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