Which geographic feature was most important to the development of both Egypt and Mesopotamia

states began imposing duties on each other's goods. congress had no way to raise money for an army to expel them.

which time period is this? or is this story fictional, i'm going to need more info to answer this question

(202 bc - 220 ad) dynasty started by lui bang; a great and long-lasting rule, it discarded the harsh policies of the qin dynasty and adopted confucian principles; han rulers chose officials who passed the civil service exams rather than birth; it was a time of prosperity