There was no absolute chronology in the ancient world and most ancient kingdoms like those of the Neo-Assyrians and Neo-Babylonians simply recorded the year of a king’s reign in their chronicles – in fact, the Neo-Assyrians used the successive number of the king’s annual campaign (palû) – which, it turns out, were not always annual. Similarly, in the kingdoms of Israel and Judah, the year was measured by the regnal year of the king, and in the books of Kings and Chronicles, these were held up against one another, thus providing a relative chronology - albeit a chronology that needs much work to unravel.