The origin of the Book of Judith has been debated for thousands of years, and is often assumed to have been written in Greek as anti-Hellenic propaganda during the Maccabean Revolt. It isn't clear why an anti-Hellenic book would have been written in Greek by an Aramaic-speaking people, however, no ancient copies of it survive in Hebrew, Aramaic, or Phoenician (Samaritan / Judahite). There are Hebrew translations, however, they are dated to the middle ages, 1000 years after the oldest surviving copies of the Judith found in the Septuagint. The Greek translations are remarkably consistent compared to the radically different versions of the Book of Tobit in the surviving copies of the Septuagint.
The name of the king in the book of Judith is named Nebuchadnezzar, which was the name of the king of Babylon, between 605 and 562 BC. However, other than the name of the king, no other elements of the story indicate the story originated with the Babylonians. Nebuchadnezzar did not fight the Medes, and could not have killed the king of Media, as the two countries were close allies at the time, and under King Cyaxares the Median Empire reached its peak. Nebuchadnezzar didn't launch a war against the Elamites, who in fact fell under the control of Cyaxares's Median Empire. As the name Nebuchadnezzar was used to replace Achiacharos in the book of Tobit, when the Sinaiticus version was simplified into the Vaticanus version, it's likely that the name Nebuchadnezzar was simply used to replaces an older name as well.
There are several indicators in the book that point to the original king being Ashurbanipal, the king of Assyria between 668 and 627 BC. Ashurbanipal did fight two wars against Elam, and virtually annihilated the Elamites in the second war. Ashurbanipal also invaded Media, and during the fighting the Median king Phraortes was killed, allowing Ashurbanipal to claim victory, even though he didn't consolidate his victory and integrate Media back into the Assyrian Empire. When Ashurbanipal had launched the invasion of Media, in his 17th year, he ordered the local kings from across his empire to send troops to the war, but almost all refused, which was a general insurrection. Therefore, while committed to the war against Media, after defeating the Medians, he was eager to return to Assyria, and restore order to his empire.
