Categorizing them by country of origin isn’t great. Focus on their actions, not their identities. If they did different actions, they wouldn’t be a problem. If some of them act differently, then they don’t deserve to be grouped together.
When coworkers (with no authority over you) do stuff like this, here’s the steps to end their behavior:
- Document everything. If you can (legally in your area, and are allowed by any employment contracts) surreptitiously audio record, video record, or photograph them, do it. If you can’t, a written log is usually sufficient.
- Don’t ever follow their instructions when they try to be your boss. Tell them you’ll just check real quick with your supervisor first to make sure that’s what he/she wants. Or just pretend they’re not talking.
- Go to your immediate supervisor. Don’t reveal about the recordings, but do read at least part of your list.
- If your supervisor doesn’t make them stop, go to their supervisor (or as high as you’re comfortable). If your company has an HR department, include them.
- If it still doesn’t stop, start polishing your resume and getting interviews. No point wasting your time where they allow this.
- if you don’t like #5, you could try legal action.