The Three Hundred and Thirty Five Years’ War (1651–1986) was a war between the Netherlands and the Isles of Scilly (located off the southwest coast of the United Kingdom). The war originated during the Second English Civil War which was fought between the Parliamentarians and the Royalists from 1642 to 1652. Parliamentarian Oliver Cromwell fought the Royalists to the far edges of England, forcing the Royalist Navy to retreat to the Isles of Scilly. The Isles of Scilly was owned by John Granville who was a Royalist. The Netherlands’ navy was allied to Parliamentarians and since Great Britain helped Netherlands during the Eight Years’ War and aided in Dutch independence from Spain, Netherlands decided to keep alliance with Britain and eventually took sides with the Parliamentarians who were more likely to win the Second Civil War.
The Royalist fleet that was stationed in Scilly managed to inflict heavy damage on the Dutch Navy. On 30 March 1651, Admiral Maarten Harpertszoon Tromp of the Dutch Navy arrived in Scilly to demand reparation from the Royalist fleet for the Dutch ships and goods taken by them, and receiving no satisfactory answer, he had declared war on them. In June 1651, soon after the declaration of war, the Parliamentarian forces forced the Royalist fleet to surrender. The Netherlands fleet, no longer under threat, left without firing a shot. However the Dutch did not officially declare peace. The war said to have been extended by the lack of a peace treaty for 335 years without a single shot being fired, which would make it one of the world’s longest wars and the war with the no casualties.
In 1985, Roy Duncan, historian and Chairman of the Isles of Scilly Council, wrote to the Dutch Embassy in London to dispose of the myth that the islands were still at war. Embassy staff found the myth to be accurate and Duncan invited the Dutch ambassador Jonkheer Rein Huydecoper to visit the islands and sign a peace treaty. Peace was declared on 17 April 1986, 335 years after the “war” began. The Ambassador joked that it must have been harrowing to the Scillonians “to know we could have attacked at any moment.”