Night sky over tomb of Cyrus the Great. Venus and the constellations Orion, Taurus, and Auriga in the night sky over the 2500-year-old tomb of Cyrus the Great, Pasargadae, Iran. Cyrus the Great was the founder of the Achaemenid Empire. The Achaemenid Empire was the world's largest ancient empire. It was founded in the 6th century BC by Cyrus the Great and lasted until it's collapse in 330 BC, under the leadership of Alexander the Great. Pasargadae was the Empire's capital.