List of ancient great powers
The Sassanid Empire is the name used for the fourth Iranian dynasty, and the second Persian Empire (226–651). The empire's territory encompassed all of today's Iran, Iraq, Armenia, Afghanistan, eastern parts of Turkey, and parts of Syria, Pakistan, and large parts of Caucasia, Central Asia and Arabia. During Khosrow II's rule in 590–628 Egypt, Jordan, Palestine, Lebanon were also briefly annexed to the Empire, as well as far west as western Asia Minor. The Sassanid era, encompassing the length of the Late Antiquity period, is considered to be one of the most important and influential historical periods in Iran. In many ways the Sassanid period witnessed the highest achievement of Persian civilization. The empire is furthermore known for being the arch-rival of the neighboring Roman–Byzantine Empire for a period of over 400 years. As the Parthians were replaced by the Sassanids, they carried on the already century long lasting Roman–Persian Wars, which would eventually become the longest conflict in human history.
Ancient history
The Achaemenid Empire was the largest and most significant of the Persian Empires, and followed the Median Empire as the second great empire of the Iranians. It is noted in western history as the foe of the Greek city states in the Greco-Persian Wars, for freeing the Israelites from their Babylonian captivity, for its successful model of a centralized bureaucratic administration, the Mausoleum of Halicarnassus (one of the Seven Wonders of the Ancient World), and for instituting Aramaic as the empire's official language. Because of the Empire's vast extent and long endurance, Persian influence upon the language, religion, architecture, philosophy, law and government of nations around the world lasts to this day. At the height of its power, the Achaemenid dynasty encompassed approximately 8.0 million square kilometers, held the greatest percentage of world population to date, stretched three continents (Europe, Asia and Africa) and was territorially the largest empire of classical antiquity.
Parthia was an Iranian civilization situated in the northeastern part of modern Iran. Their power was based on a combination of the guerrilla warfare of a mounted nomadic tribe, with organizational skills to build and administer a vast empire – even though it never matched in power and extent the Persian empires that preceded and followed it. The Parthian Empire was led by the Arsacid dynasty, which reunited and ruled over significant portions of the Near East and beyond, after defeating and disposing the Hellenistic Seleucid Empire, beginning in the late 3rd century BC. It was the third native dynasty of ancient Iran (after the Median and the Achaemenid dynasties). Parthia had many wars with the Roman Republic (and subsequently the Roman Empire), which marked the start of what would be over 700 years of frequent Roman-Persian Wars.