In what ways did the expansion of islam affect the prosperity of groups in east africa?

the great wall of china worked as a defense for the feudal states of the zhou dynasty to the north. during the warring states period more walls were put up to defend the borders of the different kingdoms. it was semi successful because despite the wall, the mongols eventually conquered china also the great wall provided protection to the economic development and cultural progress, safeguarded the trading routes such as the silk road, and secured transmission of information and transportation. @jayxboof

the lowest among the social higher rank were the working class. this class remained detached to the political progression   of the country and was hostile to the other two classes