Complex sentence: Nebuchadnezzar was the eldest son and successor of Nabopolassar, an Assyrian official who rebelled and established himself as king of Babylon in 620 B.C; the dynasty he established ruled until 539 B.C, when the Neo-Babylonian Empire was conquered by Cyrus the Great.
Split into simpler sentences: Nebuchadnezzar was the eldest son and successor of Nabopolassar, founder of the Neo-Babylonian Empire. Nabopolassar was an Assyrian official who rebelled and established himself as king of Babylon in 620 B.C; the dynasty he established ruled until 539 B.C, when the empire was conquered by Cyrus the Great.