The defeat of Jerusalem by Babylon and the exile of its top people in 586 BCE followed. Chapters 40 to 55 are given to the Jews in exile, telling them about the hope of return. This was the time of king Cyrus the Great – in 559 BCE he became ruler of a small kingdom in what is today Iran. By 540 he ruled a big empire from the Mediterranean to Central Asia, and in 539 he conquered Babylon. Isaiah's predictions of the fall of Babylon and his talk about the glory of Cyrus as one who would help Israel mean these prophecies are about the period of 550–539 BCE.