Cornwall. The oldest of English duchies (from 1337, though first a Norman earldom c.1140) has dimensions other than its peninsularity: the bulk of the course of the south-flowing Tamar forms the county boundary with Devon (some 45 miles), and but for the hills in which it rises could be canalized with the Marsland stream to render Cornwall an island. As the distant part of ‘civitas Dumnonia’ the Romans may not have colonized Cornwall (any more than later Germanic invaders), but they monopolized its tin production as they did more precious metals elsewhere; and there is some evidence for a road system, including a link between Padstow and Exeter (Isca). For Cornish people England is entered by crossing the Tamar, and in the Civil War, redoubtably though Cornish levies defended the crown within the county, they could not be brought to do so further east. Cornwall has a place in western prehistory at least as far back as the 3rd millennium bc, and in the 5th–6th cents. ad a church coloured by Irish and eastern Mediterranean practice; in later centuries it had a role not only in trade but in pilgrimage routes to southern Europe. Penzance is equidistant between Loch Foyle in Ulster and the Gironde; more intimately, perhaps, between Waterford and Quimper in Brittany. In the 5th cent. ad Brittany received an immigration from Dumnonia (Britons), and the disused Cornish language may still be studied in Breton schools. The Isles of Scilly, ‘a drowned landscape’ integral to Cornwall's prehistory, lie on the same longitude as Ardnamurchan Point in Argyll and Cadiz; and, by extension, Cornwall has had its share in the evolution of the Atlantic world. The Falmouth mail service developed a proud record on its American run 1688–1850, and in the 19th cent. Cornish miners worked, and died, in the mines of South America and South Africa; in 1901 Marconi, in Newfoundland, received the first transatlantic radio transmission from Poldhu near the Lizard. Back home, it had taken all Brunel's genius to bridge the Tamar at Saltash 1857–9, and so bring the railway, and a holiday industry, to Cornwall.

Cornwall's geology is predominantly granite and slate, the latter used for walls as well as roofs, but china clay, around St Austell, is its one extractive industry today. In antiquity tin from Cornwall's streams, increasingly deep-mined by the later 16th cent., was the region's life-blood. As ingots the metal was exported far and wide, but the earliest traders appear to have used the two north coast havens, St Ives-Hayle and the Camel estuary, rather than those on the south coast towards which most of the tin-bearing streams flowed: while the western shores of Falmouth's estuary have rendered up hoards of Roman coins (in payment?), no place in Britain is so overwhelmingly rich in the remains of 5th–6th-cent. Mediterranean pottery (import containers?) as is Tintagel, on present evidence the prime entrepôt for this epoch. Few, if any, British sites have more romance and mystery than this inhospitable headland: its history prior to the cliff-hanging castle built there by Earl Richard of Cornwall in the 1230s is at best elusive, and associations with ‘ King Arthur’ are solely attributable to the chronicler Geoffrey of Monmouth, writing a century earlier. Not a vestige of corroborative evidence has surfaced since his time. More prosaically, at the time of Domesday Book (1086), in which neither Tintagel nor tin receive mention, Cornwall was evidently underpopulated on the scale of one man per 160 acres. In 1346, however, Fowey was able to send over 40 ships to aid Edward III at Calais; in Armada year (1588) the port had only one ship in Queen Elizabeth's service, though Cornwall had become one of the most populous of southern counties. Its present-day population is some 480,000, much the most concentrated urban area being Redruth–Camborne. Truro (18,000) only became a centre in the early 19th cent., its cathedral, built 1890–1910, marking Cornwall as a diocese independent of Exeter for the first time in a millennium.

Domesday Book may confirm that Anglo-Saxon Cornwall was underdeveloped, but the special status of the tin-miners may have been established before the Conquest. When, in 1201, King John granted them their first charter confirming exceptional legal autonomies, in the Court of the stannaries, agriculture in Cornwall, which had once been exiguous, needed to give way to the territorial requirements of the tin-streamers; with the dukedom's establishment in 1336 their rights came under royal wardenship, though the court itself was only formally wound up in the mid-19th cent. By the 16th cent. the leading county families, Rashleighs, Eliots, Godolphins, formed closely knit groupings to which the Tudor monarchs were ready to respond by granting enfranchisement to some fifteen additional boroughs, including Bossiney and Penryn, famed respectively for their slate and granite quarries. The measure of their political evanescence, however, may be gauged by the Great Reform Act of 1832 which disfranchised almost all of them, a quarter of the total number (56) which were then abolished in England and Wales. But great houses, Lanhydrock, Cotehele, Trerice, still attest to no mean aristocratic pride. By the end of the 18th cent. Cornishmen of a different stamp emerged: John Opie, the precocious portraitist and art theoretician, Richard Trevithick, wrestler and inventor of high-pressure steam traction, Humphry Davy, perfecter of the miner's safety lamp. In the 19th cent. Robert Hunt became professor of London's School of Mines, a fellow of the Royal Society, and a stalwart supporter of the Royal Institution of Cornwall (1818) and the Polytechnic Society of Falmouth (1833). Such bodies sustained self-awareness in a county which, 150 years before, had been favoured with the first large-scale map of any English county. Today, though the pilchard no longer thrives along their coasts and their deep mines are derelict, the Cornish retain their cultural richness. Britain and the wider world would be poorer without their artists and potters, their cream, and Mr Lemon Hart's rum.

David Denis Aldridge

Cornwall County in sw England, on a peninsula bounded by the Atlantic Ocean, the English Channel and Devon; the county town is Truro. Major towns include Bodmin, St Austell and Penzance. A rocky coast with hills and moors inland, it is drained by the Camel, Fowey, Tamar, and Fal rivers. It is a popular tourist region. Area: (including Scilly Isles) 3512sq km (1356sq mi). Pop. (2000 est.) 499,400.