I disagree.
Zoroaster lived before Moses. Moses is dated to about 1000 B.C. or so.
Also, there is cryptic evidence in the Bible that the early Israelites were indeed polytheistic. There is the dual term used in the Old Testament for God - Yahweh, a singular, and Elohim, a plural. There was evidence that the early Isrealites even thought God had a female consort. The constant referral to the threat of polytheistic cults arising in Israel indicated that there was a sizable percentage of the Israelites who had rejected or never really had been receptive to monotheism, as also indicated by the constant chiding by the various Prophets against this behavior.
Before the Babylonian Captivity, Yahweh was considered a the National God of the Israelites. AFTER the Babylonian Captivity, the Israelites came to view Yahweh more as the only real God rather than a mere tribal Deity.
During the Babylonian Captivity, the Israelites were exposed to Zoroastrianism, which was a pure monotheism. Zoroastrians view Ahura Mazda, the name they use for God, as the only true God, the God of everyone and everything. They also believe in an evil force, Ahriman, who seeks to deceive and mislead men from the truth, they believe in an afterlife, a last judgement, a resurrection of the dead, and angels. Finally, Zoroaster predicted the coming of a Saviour who would lead all men to the truth and redemption. Its believed by many scholars that the Three Wise Men of the New Testament were Zoroastrian priests looking for the promised Saviour. All of these were missing in early Old Testament writings - in whole or in part - and indeed, some of them are more common in Christianity today than in contemporary Judaism.
No...
...there isnt. /smirk
Yes, but the one God was worshipped before Moses, indeed back to the time of Abraham.
There was evidence that the early Isrealites even thought God had a female consort
As you attest, you will find evidence of many kinds of straying by various Israelites; indeed these disobedient ones are a significant theme in the Old Testament to contrast to obedience to the ONE true God who is promoted throughout. The underlying religion was always monotheistic. The fact that the prophets spoke out about deviant behavior and attempted to draw them back to worship of the one, true God shows clearly that monotheism was alive and well. That many were straying toward OTHER religions does not negate the fact that the ISRAELITE religion as revealed well before Moses, was monotheistic.
The historical Zoroaster overall is not disputed (there are a few who think that he did not exist); but when he lived is. The Avesta language used in the Gathas (which he is purported to have written or sung), is considered an archaic Persian language probably dating to about 1000 BC as you state. That is not the same as saying when he created these poems / scriptures (they could be even earlier).
Moses probably lived around 1400 BC, not 1000 BC which dates to the kingdom of Saul and David. While the Old Testament scriptures as we have them, probably went through an editorial process during or after the Babylonian exile, there are quite a few examples of verses or people named from the Bible before the exile (usually on pot shards).
Although the Old Testament is full of references to paganism (idolatry), it is always condemned. Clearly the scriptures talk about only a remnant being faithful to the one God Yahweh. Elohim is really a title for God which meant lord in old Northwest semitic languages. Elohim essentially means Lords(which Christians point to for proof of the trinity). Yahweh has lots of titles such as provider, protector, Lord, etc... Lots of people have confused the titles with His name and therefore think there are multiple gods or syncretistic with other religions or peoples. I am not saying you are saying that (and sorry if I am saying stuff you already know).
According to most secular Biblical scholars, there are at least 4 or 5 different sources for the Old Testament that were edited after or during the exile, one is called E for Elohim and another is J for Jehovah or Yahweh. The same techniques for document deconstruction are actually used on the Zoroastrian scriptures as well and lead to a terminus date of about 1000 BC date for the original composition of the Gathas. Since the earliest extant scriptures for the Zoroastrian religion are during classical times (that I know of), I would say everybody should be cautious on stating definitive dates for his life. Clearly the name for the God Yahweh is older man called Zoroaster. The name was attested to in Urgarit from about 1400 BC and other places in Syria.
Sorry about the book :)