Lord Warden of the Stannaries
The Lord Warden of the Stannaries used to exercise judicial and military functions in Cornwall, England, and is still the official who, upon the commission of the monarch or Duke of Cornwall for the time being, has the function of calling a stannary parliament of tinners. The last such parliament sat in 1753.
Source: Wikipedia — Lord Warden of the Stannaries (CC BY-SA 4.0)