Isle of Man currency. The Isle of Man, also known as Mann, is a self-governing Crown Dependency of the United Kingdom. Queen Elizabeth II is the current Lord of Mann. Although not a part of the United Kingdom, the U.K. is responsible for foreign relations and defense. The capital and largest city is Douglas. Monetary system: 1 Pound = 20 Shillings (to 1971); 1 Pound = 100 Pence (from 1971).