Final answer:
Rome's less rugged landscape compared to Greece allowed for easier expansion and unification of the Italian peninsula.
Step-by-step explanation:
A less rugged landscape than that of Greece facilitated the unification of the Italian peninsula under Roman control. Unlike the Greek city-states, which were often isolated from each other due to the mountainous terrain, Rome's central location and less daunting topography allowed for easier expansion and movement. Thus, Rome was able to easily unify the whole Italian peninsula, leading to the establishment of a vast and powerful empire.