After the Great Apocalypse or World War 111 as some called it the human population was devastated the use of nuclear and biological weapons killed millions and worst turned others into mutants. The humans were having a hard time trying to bring some order back to the World, It was then that the so called 'Fantasy creatures' who had always been in the background decided to come out into to the open and help their human brothers. I will say they were a bit surprised to have creatures of folk law suddenly turn up at what was left of places of authority saying "Where here to Help". After the shock had worn off and the need to get the lawless times under control it was understandable humanity welcomed them, the fact that we out numbered them was not missed by some.
Now being that the army and police forces were near to nonexistent and other emergency services were hard press to help the Centaurs put forward that all services should be joined into one body that could handle all situations that should arise and erase the rivalry that was plaguing them, not being able to come up with anything better the humans agreed but only if a neutral like the Centaurs ran it. The Elves wanting to help in the medical services agreed with the idea and that the Centaurs should run it with their history of wisdom and leadership from times past though the Elves did suggest it should be called 'The Rangers' something from Elf history.
The Rangers consisted mostly of centaurs (mostly mares), humans,some elves and whatever other folk law being who wanted to help, I must mention the centaurs have more females than males so until that improves the males are held back from patrolling.
The mission of the rangers has been to reestablish contact and communications with any pockets of civilization, reestablish and uphold the law. Control the mindless mutants roaming the old cities and the wilds. Find any and all usable tech no matter what it is to be brought back for reuse.
Over time they became the main carries of the law settling grievances or judgements in the townships that formed up away from the decaying old cities and the name Centaur Rangers became popular so it became official.
THE END (for now)