Conquest contributed to growth of different organized empires which contributed to expansion of trade, postal network, road network and administration which was well organized.
There were other empires which contributed to the conquest. For example,
1. Persian empire which linked the west and east, and also cultural diffusion.
2. Athenian empire which kept the pirates away and the persian defeat.
3. Ptolemaic empire contributed to trade lines to be built up and also new ports which were built during that empire period.
