Their "roots" were already polytheist. Monotheism was a late development which was apparently stronger at first among the nomadic herdsmen population than in the cities. If you have a different order of events, you have a scoop.
Israel was monotheist. Remember? This is what gave Abraham special favor with God, he left the many gods to hold Faith in one God. Have you read the Old Testament?
I have no evidence that proto-celtic metal working differed in any significant way from that of the Israelite tribes in Egypt, or any influence that Egyptian technology had on Israeelite technology. Do you? Can you show me examples?
Haven't I already shown you that the language issue is unreliable in prior posts? Where is your examples of language in the Halstatt and La Tene relics? Where did the peoples of Halstatt and La Tene come from? People don't just appear out of thin air. Archeologists have no answers to these questions, and neither do you, evidently.
Current knowledge of ancient cultures and movements are foggy at best and the interpretations thereof are speculative at best. And none of it to date has taken into consideraton the writings on the Assyrain tablets. So what you have is allegations made using incomplete data.
When you factor in all the existing evidence plus all the unanswered questions, you have the peoples of the Western world as the prime candidates for the remnants of the Northern Kingdom, in spite of any small details in interpretation of ancient findings.
I keep asking you, and you keep avoiding. What people would you pick for the descendents of the Northern Kingdom?
You're bizzarely and blindly plowing ahead, ignoring the hundreds of years of non-cult scholarship. You've already explained what's going on. It's a cult thang, we wouldn't understand. There's not much more to it than that. Why pretend?
You've invoked the right to ignore all inconvenient differences, which covers basically all the evidence that there is. Most scholarship--I can GoogleTM, you can GoogleTM--thinks the Celts had a distinct culture parallel and not subsequent to the Hebrews. They think they can tell from the archaeological record in a given spot when it replaced pre-existing culture. Most of those replacements are too early for your story, to the extent that you have a story. That material is there for anybody. I'm not going to dump a bunch of it on this thread because you've already reserved the right to wave away evidence of such nature in advance.
You have failed to tell a coherent story of how the Semitic Hebrews are supposed to have become the seemingly-already-dispersed-in-Europe Indoeurpean Celts. I have tried to prompt you to address some of the deficiencies of your account, but you seem to think the ball is in my court.
All I'm pointing out is that what you're scoffing away is everything we know. Nothing in your few data points of record justify the wild tale you're telling. You've extrapolated all of it. You attempt to bludgeon with your ability to misunderstand or instantly forget everything that has been learend outside of your special cult insights.
That's the formula for preaching to the choir. You'll never reach a single non-believer by pretending to be puzzled at why your performance is unconvincing.