As the cold war neared its end at the top of the 1980s a lot of countries turned inward to try and figure out how to deal with their domestic problems. The growing mutant population was certainly a topic of contention among the ruling parties of government, and they openly debated the possibility of registration and control. When brought up the more vocal elements of the Mutant community spoke up against it, comparing it to fascist regimes in the not-so-distant past and arguing that this sort of discourse seemed to fit more with the powers that be behind the iron curtain.
Some of those louder voices radicalised and splintered off from the more peaceful diplomatic approach some of the older leaders had. A prominent example is the Sherwood Rangers, a small group of mutants that claims that the established elite would take everything from them if they were unopposed. So under the guise of one of the United Kingdom’s most well-known folk legends, they banded together, and in early 1992 they started to take aggressive actions against known anti-mutant legislators and organisations.
Earliest activity of this organisation has been attributed to the man known only as Robin Hood, who allegedly broke into a maximum security prison to liberate now fellow Ranger Heather R. a.k.a. Maid Marian. Together they've gone on to claim several terrorist attacks in the City of London as well as a hand in the Halloween night terror that saw (latent) mutant abilities boosted by a mysterious surge. Their current whereabouts are unknown.