The area referred to today as southeast asia was at one time 1)arabia 2)the mongol empire 3)the khmer empire 4)on marco polo's route

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

they united the colonies in their fight against the british.