How did geography affect Greek and Persian civilizations differently during the classical era?

Greek was a region of mountains. The region of Greece resulted in independent city-states. This resulted in the start of wars between the city-states as they were not unified as one. The nearness to the Mediterranean allowed them to become a dominant power commercially with other regions.

Persia, unlike Greek was unified and had less in-state wars. The area of the Persian Empire was rather large, and sometimes it became a tough job ruling it.