[30] Both geographic and historical factors distinguish the Cornish as an ethnic group[31] further supported by identifiable genetic variance between the populations of Cornwall, neighbouring Devon and England as published in a 2012 Oxford University study.

[32] Throughout medieval and Early Modern Britain, the Cornish were at some points accorded the same status as the English and Welsh and considered a separate race or nation, distinct from their neighbours, with their own language, society and customs.

[37] Structural changes to the politics of the United Kingdom, particularly the European Union and devolution, have been cited as the main stimulus to "a growing interest in Cornish identity and distinctiveness" in late-20th century Britain.

[64][65] A 2015 study found that modern Cornish populations had less Anglo-Saxon ancestry than people from central and southern England, and that they were genetically distinct from their neighbors in Devon.

[66] Throughout classical antiquity the Celts spoke Celtic languages, and formed a series of tribes, cultures and identities, notably the Picts and Gaels in the north and the Britons in the south.

[74] The Sack of Rome in the year 410 prompted a complete Roman departure from Britain, and Cornwall then experienced an influx of Celtic Christian missionaries from Ireland who had a profound effect upon the early Cornish people, their culture, faith and architecture.

[72] The Angles, Jutes, Frisii and Saxons, Germanic peoples from northern Europe, established petty kingdoms and settled in different regions of what was to become England, and parts of southern Scotland, progressively defeating the Britons in battle.

[61] However, the Duchy of Cornwall gradually lost its political autonomy from England, a state which became increasingly centralised in London,[21] and by the early-Tudor period the Cornish had begun to see themselves as "a conquered people whose culture, liberties, and prosperity had been downgraded by the English".

The rebellion was initially a political march from St Keverne to London led by Thomas Flamank and Michael An Gof, motivated by a "mixture of reasons"; to raise money for charity; to celebrate their community; to present their grievances to the Parliament of England,[91][92] but gathered pace across the West Country as a revolt against the king.

[95] In the rebellion, separate risings occurred simultaneously in Bodmin in Cornwall, and Sampford Courtenay in Devon—which would both converge at Exeter, laying siege to the region's largest Protestant city.

[104] On 21 February 1804, the world's first locomotive-hauled railway journey took place as Trevithick's unnamed steam locomotive hauled a train along the tramway of the Penydarren ironworks, near Merthyr Tydfil in Wales.

[105] Cornwall, the United Kingdom's only region with a subtropical-like climate,[106] became a centre for English tourism, its coastline dominated by resort towns increasingly composed of bungalows and villas.

[106] This, coupled with the rise of Romantic nationalism in Europe inspired and influenced a Celtic Revival in Cornwall,[107] a social, linguistic and artistic movement interested in Cornish medieval ethnology.

[106] The Cornish people are concentrated in Cornwall, but after the Age of Discovery in the early modern period were involved in the British colonisation of the Americas and other transcontinental and transatlantic migrations.

[21] Increased competition from Australia, British Malaya and Bolivia, coupled with the depletion of mineral deposits brought about an economic decline for Cornish mining lasting half a century, and prompting mass human migration from Cornwall.

[10][21] In each decade from 1861 to 1901, "around 20% of the Cornish male population migrated abroad"—three times that of the average of England and Wales—and totalling over a quarter of a million people lost to emigration between 1841 and 1901.

[10] There was a displacement of skilled Cornish engineers, farmers, merchants, miners and tradesmen, but their commercial and occupational expertise, particularly in hard rock mining, was highly valued by the communities they met.

[116] However, the global connections of the remaining Cornish diaspora, which is concentrated in English-speaking countries such as Australia, Canada, South Africa and the United States, are "very strong".

[122] The Kernewek Lowender is the largest Cornish festival in the world, held in the Kadina, Moonta and Wallaroo towns on the Yorke Peninsula, which attracts tens of thousands of visitors bi-annually.

[14] Following their sea voyage they attempted to dock at Veracruz but were forced away by the Spanish to a beach at Mocambo from where they hauled their machinery through jungle and swamp to Santa Fe.

[14] The fever forced the survivors to abandon their equipment and head inland up into the mountains to Xalapa to try to escape the mosquitos for three months, until the end of the rainy season.

[124] Although an international gold rush, the Cornish overwhelmingly formed the skilled labour force in the Witwatersrand, until the outbreak of the Second Boer War prompted a retreat.

[138] Early medieval Cornwall was associated with the Matter of Britain, a national myth recounting a legendary Celtic history of Brittonic warriors, including King Arthur.

[17][27] The Matter of Britain was supported by texts such as the Historia Regum Britanniae, a pseudohistorical account of the history of the ancient Britons, written in the mid-12th century by Geoffrey of Monmouth.

[142] Tales of these creatures are thought to have developed as supernatural explanations for the frequent and deadly cave-ins that occurred during 18th-century Cornish tin mining, or else a creation of the oxygen-starved minds of exhausted miners who returned from the underground.

[143][144] In the 1780s, John Opie was the first Cornish-born painter to gain widespread attention; his work was exhibited at the Royal Academy and he was described by Joshua Reynolds as "like Caravaggio and Velázquez in one".

[145] Artists who appreciated the quality of Cornwall's natural light, such as J. M. W. Turner, began to visit, with more following after the opening of the Great Western Railway, including Whistler and Sickert.

[146] Early Christianity is thought to have existed in Cornwall during the 1st century, but limited to individual travellers and visitors, possibly including Priscillian, a Galician theologian who may have been exiled to the Isles of Scilly.

[150] Stargazy pie is an occasional festive Cornish dish with the heads of fish standing on their tails, originally pilchards, piercing a pastry crust.

A study was carried out Willett, JMA; Tidy, R; Tregidga, G; et al. through Exeter University [169] using data from January to April 2017 to understand why Cornwall voted leave in the Brexit referendum when it benefitted greatly from EU funding, such as the Cornwall and Isles of Scilly Growth Programme [170] which was worth £600 million and supported over a hundred projects such infrastructure, agriculture, employment and low carbon initiatives.