ROMAN EMPIRE :
1. Extent: Stretched from Spain in Europe to Syria in the East along the Mediterranean Sea.
In the North the boundaries are marked by Rhine and Danube(rivers). In the south by Sahara desert.
2. It had a diverse population. There were many languages spoken here.
3. Main languages for administrative purposes: Greek and Latin.
4. Upper classes of East spoke Greek and those of South spoke Latin.
IRANIAN EMPIRE :
1. Extent: entire area south of Caspian sea to Eastern Arabia.
2. It did not have a much diverse population.
3. There were 2 diverse dynasties that ruled over Iran, the Parthians and the Sasanians.
4. Most of the people spoke Persian language.