Smuggling is understood to have prospered since Polperro developed as a port in the 12th century. It reached its zenith in the late 18th century when Britain's wars with America and France precipated the high taxation of many imported goods, making it worthwhile for the local fishermen to boost their income by the covert importation of spirits, tobacco and other goods from Guernsey. Much of the success of the smuggling trade through Polperro is ascribed to the influence of Zephaniah Job (1749–1822), a local merchant who became known as "The Smuggler's Banker". A more organised Coast Guard service was introduced in the 19th century along with stiff penalties, and led to much less smuggling. Part of the South West Coast Path was originally used by Revenue Officers as they patrolled the coast in search of smugglers. Whilst the Coast Path is maintained by the National Trust, the foreshore belongs to the Duchy of Cornwall.