7. The Roman Empire

The Romans managed to effectively combine their whole empire into one unit by having great roads that went through all of the empire. The roads allowed military to move quickly and efficiantly from one side of the empire to the other. If there was any problem within the empire, or someone was attacking there would be no problem for the Roman military to go and deal with the situation. The roads also made trade easier, it would now be easier to transport useful goods through the empire. The roads played a huge part in uniting the Roman empire into one.