The sandinistas for nicaragua overthrew a 40-year dictatorship
Used the indian's land, fought with them and made them angry?
Right now, I would call them "diaspora" if they're more dispersed (Armenian diaspora is quite well-known) or a "community", for example "French community" if they're more closely in contact.
If they reject their new land's law and intend to include this land into their old one, they could be "colonizers".
It says that people have a moral responsibility to break unjust laws, and to take direct action rather than waiting potentially forever for justice to come through the courts
