Cyrus II of Persia (Old Persian: Kūruš;[5] New Persian: کوروش Kuruš; Hebrew: כֹּרֶשׁ, Modern Kōréš Tiberian Kōréš; (c. 600 – 530 BC),[6] commonly known as Cyrus the Great [7] and also called Cyrus the Elder by the Greeks, was the founder of Achaemenid Empire, the first Persian Empire.[8] Under his rule, the empire embraced all the previous civilized states of the ancient Near East,[8]expanded vastly and eventually conquered most of Southwest Asia and much of Central Asia and the Caucasus. From the Mediterranean Sea and Hellespont in the west to the Indus River in the east, Cyrus the Great created the largest empire the world had yet seen.[9] Under his successors, the empire eventually stretched at its maximum extent from parts of the Balkans (Bulgaria-Paeoniaand Thrace-Macedonia) and Eastern Europe proper in the west, to the Indus Valley in the east. His regal titles in full were The Great King, King of Persia, King of Anshan, King of Media, King of Babylon, King of Sumer and Akkad, and King of the Four Corners of the World.
Hope this helps!