When did the Persians dominant powers?

The Persians emerged as a dominant power in the 6th century BCE, particularly under the rule of Cyrus the Great, who founded the Achaemenid Empire around 550 BCE. This empire expanded significantly, reaching its height under Darius I and Xerxes I, encompassing large parts of the Near East, Egypt, and parts of India and Europe. The Achaemenid Empire remained a major power until its conquest by Alexander the great in 330 BCE.