A lot of the land that we might use for wild camping is termed common land, but as has been pointed out on numerous occasions, every bit of land is owned by someone. However, it wasn’t always like this. Two hundred and fifty years ago, considerable tracts of land were truly common land. Then came two hundred years of Inclosure (apparently the correct spelling) Acts, over 5,000 of them, which effectively confiscated the land (with no compensation) from the common people. By 1875 over half the agricultural land in England and Wales was owned by about 2,000 people.
Obviously it is impossible to go back and right the wrongs of the past 250 years. However, giving us (back) the right to wild camp on formerly common land would be a gesture of some recompense for the deeds of a greedy few visited on our forefathers.
Some links to read:
Wikipedia , How the English people became landless, National Archives