Nebuchadnezzar was the oldest son of Nabopolassar, the founder of the Chaldean Empire. After serving as commander of the army, Nebuchadnezzar became king upon his father's death in August of 605 B.C. By marrying the daughter of Cyaxares, he united the Median and Babylonian dynasties. He wasn't just a warlord, he was also skilled in politics.
During Nebuchadnezzar's time, Babylon was the largest city of the world. It has been estimated to have covered over 2,500 acres (10,000 hectares), with the Euphrates River flowing through it. The name of the city came to symbolize the entire empire.
Nebuchadnezzar is best known to students of the Bible for his defeat of the southern kingdom of Judah (the northern kingdom of Israel was by then long gone, having been conquered and deported over a century earlier by the Assyrians - see Ancient Empires - Assyria). By 586 B.C., the Babylonian forces conquered the land, devastated Jerusalem, looted and burned the original Temple that had been built by Solomon (see Temples and Temple Mount Treasures), and took the people away into what became known as the "Babylonian Exile." (2 Kings 25:1-17).
As powerful as Nebuchadnezzar was, he did not conquer the people of Judah of himself. God didn't just allow it to happen, He actually brought it about. (2 Chronicles 36:15-20). The people had become extremely corrupt and idolatrous. They ignored all of the Prophets that God had sent to warn them (2 Chronicles 36:15-16), and they refused to repent. They trusted in themselves, in the city of Jerusalem, even in the physical Temple, rather than in The Lord Himself. So, God, through Nebuchadnezzar, destroyed it all in order to make them realize, in no uncertain terms, that they had turned their backs on Him (see Why Babylon?).
Among the Jews who were deported from Judah to Babylon was a certain young man known as Daniel. From him, and the Bible book that carries his name, we get some of the most sensational prophecies for our time now. See Daniel's Statue
Fact Finder: Were the prophecies given to Daniel for his time, or the end-time?