Persia
In 539 BC, King Cyrus seized the city of Babylon, supported and aided by the priests of Marduk, who disagreed with the religious policies of the Babylonian king Nabonides. The Persian Empire, organized into satrapies, then clearly encompassed the various territories that attested to a Judean and Israelite presence. Egypt was a special case, as it often rebelled against the Persian authorities. Chances are that the Judeans of the Delta and Elephantine were loyal to the Persians, which undoubtedly provoked hostility from the Egyptians. This context may also explain why the Exodus plays such an important role in the Pentateuch : the Persian authorities would no doubt have been pleased to learn of the existence of a story in which the god Yhwh triumphed over the Egyptians.