Why was Enfield Chase called a royal hunting ground?

Answer 1

Because the King of England at that period in history decided that only he could hunt in that area, as literally, all land in England is considered as owned by the monarch, who thens parcels off different places to his barons and earls and whoever, and they take care of that land, collect taxes from the local population, etc. At one point, the King probably went hunting with the local baron, and had a good time, so it became a 'royal hunting ground'; punishments were given for any local peasants hunting food for their families, and helping give rise to stories of Robin Hood and his band, who did hunt the "king's deer"