Final answer:
The Proclamation of 1763 angered the American colonists because it prevented them from settling in western lands and violated their rights to property and self-governance.
Step-by-step explanation:
The Proclamation of 1763 was a British law issued after the French and Indian War. It stated that colonists were not allowed to settle west of the Appalachian Mountains. This angered the American colonists for several reasons. Firstly, many colonists had already settled in the western lands and wanted to expand their territories. Secondly, the proclamation was seen as a violation of their rights to property and self-governance. Finally, it fueled tensions between the colonists and the British government, as they felt their interests and desires were being disregarded.
Learn more about The Proclamation of 1763 and its impact on the American colonists