Why did most people within the Byzantine and Persian empires accept Islam so easily? They would be allowed to serve in the government positions.
They were concerned about repression by the new Muslim leadership.
Special consideration was given only to those accepting the new religion.
Trade opportunites would increase and improve their earnings.

The constant presence of diseases or infectious agents within a given geographic area or population group. it may also refer to the usual prevalence of a given disease with such area or group. it includes holoendemic and hyperendemic diseases. a holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). a hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. so probably family history.

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