Why can't Stilton make Stilton?

Stilton cheese, despite its name, cannot be produced in the Cambridgeshire village of Stilton due to Protected Designation of Origin (PDO) status. This status restricts production to Derbyshire, Leicestershire, and Nottinghamshire. Former MP Shailesh Vara is advocating to change this rule, believing historical evidence supports the village's claim to the cheese's origin. Similar protected products include Scotch Whisky and Cornwall's pasties, with strict geographical limitations for production.