My barn is notorious for switching around herds on a nearly weekly basis. I work out there, and it's amazing to see how the universal herd will just establish itself. While some cases take time, others are fairly quick. In this case, I would say that you should try to spend either more time observing or interacting with the herd your horse is in. This gives you two advantages;
1. You'll get to know the big bosses and the pecking order for the rest of the herd. This way, you'll have a better sense of who to move. If you gain the respect of a boss enough to move him, you'll in turn get respect from other horses, making them all easier to maneuver around.
2. You'll get to see where your horse lands in the system. This too will help you approach the herd as a whole and make your job much easier.
In your case, the aggression from the other horses is hard to deal with; you can't handle all of them at once. I would suggest placing him in a paddock with a lower-level horse that can teach him to share and maybe even buddy up with. Continue to introduce more horses, if the situation is safe, and eventually he will be acclimated enough to join the herd. Your horse will take time and patience, so be supportive and helpful to him.
Finally, try to ease up on weapon use. Right now, I understand that it is a safety precaution and keeps you and your horse in the best conditions. Again, I'm gonna hit on the fact that all of this takes time. As your horse grows more accustomed to a herd, you too need to become at least a joint part of it. I partially agree with Avna that badassery in the field can help, but it can also hurt. If you become known in the herd as a jerk who comes out swinging a whip at everyone, the respect is lost and replaced with fear. I have had coworkers who were new and used whips, and their connection to the herd was never as strong as mine. There was even an incident where the big boss in the herd reared up at her because she had a whip. The woman was only trying to turn him in, and from what I could tell, had no negative energy around her, but she still had the whip. In a horse's mind, that takes priority- the fact that the whip is present- and not who the holder is.
All in all, give this time. Be aware of your surroundings and use your "vibes" as I call them to feel out the presence of your horse in the group and your own presence. I wish you the best of luck!
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