ancient.eu - Ancient Persia After his father's death in 559 BCE, Cyrus the Great became king of Anshan but like his predecessors, Cyrus had to recognize Mede overlordship. In 552 BCE Cyrus led his armies against the Medes and captured Ecbatana in 549 BCE, effectively conquering the Median Empire and also inheriting Assyria. Cyrus later conquered Lydia and Babylon. Cyrus the Great created the Cyrus Cylinder, considered to be the first declaration of human rights and was the first king whose name has the suffix "Great". After Cyrus' death, his son Cambyses II ruled for seven years (531-522 BCE) and continued his father's work of conquest, making significant gains in Egypt. A power struggle followed Cambyses' death and, despite his tenuous connection to the royal line, Darius the Great was declared king (ruled 522-486 BCE).