The piece of land given to a vassal in feudalism is called the fief
O tithe
O rural
O serf

it affected it because the kingdoms (with trade) slowly got richer and richer.

attacks by the seljuk. a devastating blow to the entire byzantine world was dealt by christian crusaders from the west. the venetians were eager to destroy byzantine power and offered the crusaders money, ships, and part of the spoils of war.

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the muslim brotherhood