- Present-day Iran: The heartland of the Persian Empire was present-day Iran, where the Achaemenid dynasty originated. It included the regions of Persis (Fars), Susiana (Khuzestan), Media (Medi), and Parthia (Khorasan).
- Anatolia and the Balkans: The Persian Empire expanded westward into Asia Minor (Anatolia) and incorporated regions such as Lydia, Ionia, and Phrygia. They also extended their control over parts of the Balkans, including Thrace and Macedonia.
- The Levant: The Persians conquered the region known as the Levant, which includes present-day Syria, Lebanon, Palestine, and Jordan. They established their rule over the Phoenician cities and brought the region under Persian control.
- Egypt and Cyrenaica: The Persian Empire also conquered Egypt and Cyrenaica (present-day Libya). They ruled Egypt as a satrapy (province), and maintained control over the country until the rise of Alexander the Great.
- Mesopotamia: Mesopotamia, the region between the Tigris and Euphrates rivers, was a key territory for the Persian Empire. It included the ancient cities of Babylon, Nineveh, and Ur.
- The Indus Valley: In the east, the Persian Empire expanded into the Indus Valley, incorporating the regions of Gandhara and Sindh (present-day Pakistan and India).
- Central Asia: The Persians controlled parts of Central Asia, including areas such as Bactria (northern Afghanistan) and Sogdia (present-day Uzbekistan and Tajikistan).
It's important to note that the extent of the Persian Empire fluctuated over time and there were periods of expansion and contraction. Additionally, the empire was divided into provinces (satraps) that were governed by local rulers who paid tribute to the Persian king.