Why did british enact the proclamation of 1763?

The Royal proclamation was issued in 1763 by king George third when Great Britain won the seven years war and gained land in North America. This act prohibited the colonialists from settling west of Appalachian mountains. Its purpose was to improve the relations with Native Americans better by controlling trade, land purchases and settlements. It angered the colonialists because they already had land in that area and they wanted to expand territories in the western direction. This proclamation gave Great Britain a monopoly in all the lands bought from native Americans.

its d i know cause i've been googling it