Answer:
During the Iron Age I, the Israelite religion became distinct from the Canaanite polytheism out of which it evolved. This process began with the development of Yahwism, the monolatristic worship of Yahweh that gave acknowledgment to the existence, but suppressed the worship, of other Canaanite gods. Later, this monolatristic belief cemented into a strict monotheistic belief and worship of Yahweh alone, with the rejection of the existence of all other gods, whether Canaanite or foreign.
During the Babylonian captivity of the 6th and 5th centuries BCE (Iron Age II), certain circles within the exiled Judahites in Babylon refined pre-existing ideas about their Yahweh-centric monolatrism, election, divine law and Covenant into a strict monotheistic theology which came to dominate the former Kingdom of Judah in the following centuries.
