Which society was monotheistic?

...I didn't think any of them were. If I remember my ancient history cl correctly, which was a few years ago, The jews actually borrowed a lot of their mythology from the Babylonians because when Babylon defeated the Israelites, they still let them have religious freedom. The Egyptians, polytheistic, no brainier. Persians, I thought they were who the greeks fought against in the punic wars... wait I found something, the persians started out polytheistic but then started practicing Zoroastrianism which is monotheistic so the Persians would be your answer. Sumarians, polytheistic no brainer once again.