The term "King of Persia" refers to the rulers of the ancient Persian Empire, which was one of the largest empires in history. The most notable kings include Cyrus the Great, who founded the empire in the 6th century BCE, and Darius I, known for his administrative reforms and expansion of the empire. The Persian Empire was known for its cultural diversity and significant contributions to art, architecture, and governance. The Persian Empire reached its height under Xerxes I, who is famous for his invasion of Greece. The empire eventually fell to Alexander the Great in the 4th century BCE, marking the end of Persian dominance. The legacy of the Kings of Persia continues to influence modern culture and governance.