The Celts are a category of European peoples with a common ethnic, cultural and linguistic heritage. Many Celtic subgroups used to be adversaries of the Roman Empire, while others later embraced elements of Roman culture. Today, the peoples of Brittany, Cornwall, Ireland, the Isle of Man, Scotland and Wales make up the six Celtic nations with surviving Celtic languages. Additionally, the people of Galicia in Spain claim Celtic heritage, although no Celtic language survives in the region. As well the Celts were part of the mass migration of Europeans to North America and Oceania, so that there is a notable Celtic cultural presence in the settler societies of the post-colonial world.

Diachronic distribution of Celtic peoples:

  Core Hallstatt territory, by the sixth century BC

  Maximal Celtic expansion by 275 BC

  Lusitanian area of Iberia where Celtic presence is uncertain

  Areas where Celtic languages remain widely spoken today

Understand

When referring to the Celtic nations, peoples and cultures, the world "Celt" is most-commonly pronounced with a hard C (IPA: k), as in "cat". The concept of a Celtic culture is tenuous, and has only been used since the 18th century to refer to contemporary cultures and peoples. The Celtic languages are a branch of the Indo-European languages with some traits in common, and a recorded history back to the 6th century BC.

Roman Empire

The Dying Gaul, a Roman marble statue inspired by the Gallic Wars

Most written sources about the Celts in ancient times are from the Roman Empire. The Celts were the dominant ethnic group in Gaul (which made up France and neighbouring countries), Hibernia (Ireland) and Britannia (Britain), and were also present in Hispania (Spain) and other lands the Romans were expanding into, including as far east as North Central Anatolia, then known as Galatia after them.

In the fourth century BCE a Celtic chieftain known to history under the name "Brennus" led an army that managed to defeat and sack Rome, only withdrawing after the Romans paid a considerable ransom in gold.

The Roman Army conquered Gaul in the Gallic Wars. The Gallic peoples were Romanised, making Latin language and Roman religion dominant.

Retreat of Rome and emergence of Celtic Christianity

The Roman Empire was already Christianised before it abandoned Britannia in the 5th century. Some non-Christian, non-Celtic peoples invaded Britannia, eventually becoming the English nation. The Britons (Romanised Celts) were able to hold on to Wales, Cornwall, and for a while Cumbria. They were also able to expand into Brittany, returning some Celtic presence to the European mainland. One of these Romanised Celts from present-day Wales was abducted and sold into slavery in Ireland. After learning the language he escaped, but then returned to Ireland as a Christian preacher, and is known to history as Saint Patrick. Through the influence of Patrick and other missionaries, Ireland and Scotland became home to dozens of thriving monasteries. These monasteries were important places of refuge for the Christian religion in coming centuries, and helped to re-Christianise the European mainland after the Fall of Rome. They also had a distinct style of worship that was eventually suppressed in favour of the Roman "rite" (tradition).

Integration into non-Celtic countries

See also: Medieval Britain and Ireland, Vikings and the Old Norse, Franks

Every Celtic-speaking country was eventually overrun by non-Celtic neighbours. Notable dates in this process include the Kingdom of Brittany being demoted to a duchy and swearing allegiance to the Frankish king (942), and the first Norman invasions of Wales (1067) and Ireland (1169). Although Scotland continued to exist as a separate kingdom, it was ruled by an elite that was increasingly not culturally Celtic, being of Anglo-Norman ancestry and speaking French and Scots (not Gaelic).

In 1542 Ireland was elevated from a "lordship" to a kingdom, but with the King of England doubling as the absentee King of Ireland. The "Laws in Wales Acts" of 1535 and 1542 fully integrated Wales into English law.

Assimilation, resistance and diaspora

Britain and Ireland historical travel topics: Celts → Medieval → Early modern → Industrial Britain → British Empire

Throughout the early modern period, the land rights of Celtic peoples were constantly under attack. The old Celtic noble classes were exiled or assimilated to English and French cultures, and the peasants were then fully exposed to both economic and cultural exploitation. The last Irish nobles not loyal to England fled in the "Flight of the Wild Geese" in 1691, and the Scottish ruling class was bribed into accepting a Union with England in 1707. Land was now firmly in the hands of people, often absentee, of an alien culture and language to the majority of the peasants, resulting in the Highland Clearances in Scotland and the Great Famine in Ireland.

Some of the legacies of these tragedies were the beginnings of Gaelic diasporas in Australia, Canada, England, New Zealand, South Africa, the United States, the Caribbean and several countries in Latin America.

With the rise of standardised schooling, Celtic languages came under threat, both at home and in the diaspora. Manx and Cornish died out completely at one point but have been revived. Now only minorities in each Celtic country can speak a Celtic language varying from relatively strong Welsh, where 11% of the population are fluent and 23% can speak some, to endangered Scottish Gaelic, where only 1.1% of the Scottish population can speak it.

While much ancient Celtic literature and mythology has been lost, many modern works of fiction describe ancient Celts; usually with a patriotic theme. The French adventure cartoon Astérix, published since 1959 and widespread in Europe, describes how Gaulish villagers in Brittany achieve superhuman strength from a magic potion, allowing them to resist Roman invaders. While much of the comedy is based on puns, anachronisms and national stereotypes, the stories are well-researched, and have introduced many young Europeans to the Celtic-Roman conflict.

Talk

The Celtic languages alive today are split into two sub-families:

• the Brythonic languages: Breton, Cornish, and Welsh;
• and the Goidelic (or Gaelic) languages: Irish, Manx, and Scottish Gaelic.

The Brythonic languages are descended from Old Brythonic, which was spoken all over Great Britain before the arrival of settlers speaking other languages (mostly English, Irish, and Norse) started their fragmentation. Speakers were pushed to the northern and western margins of the island, and in the case of the Bretons, across the English Channel. The Goidelic languages are all descended from Middle Irish, which was brought to the Isle of Man and Scotland by settlers from the Emerald Isle, from which point the languages diverged.

The living Celtic languages have a similar grammar: nouns take either a masculine or feminine gender, sentences generally follow the verb-subject-object order, and "verbnouns" are used where other European languages might use infinitives or gerunds. All six languages also share a vigesimal (base-20) counting system, and display a phenomenon called mutation which causes changes to the initial consonants of words under various grammatical conditions.

The Brythonic and Goidelic branches have evolved separately for so long that the vocabulary similarities are often only apparent if you dig into etymologies, meaning that mutual intelligibility is low to non-existent. By contrast, there is high mutual intelligibility within the groups, particularly orally. Thus, if you speak Irish, you will very likely be able to hold a conversation with a Manx or Scottish Gaelic speaker without possessing any proficiency in those languages, but you will find it impossible to do the same with speakers of Breton, Cornish, or Welsh, who in turn could understand each other to a high degree.

Virtually everyone in Britain and Ireland is fluent in English, and Breton speakers in Brittany are also fluent in French.

There is an unknown number of extinct Celtic languages, including all of the continental Celtic languages such as Celtiberian and, most famously, Gaulish. At least two Brythonic dialects - Cumbric, once spoken in northern England, and Pictish, the language of ancient Scotland - also didn't survive the onslaught from settlers and invaders to Britain.

However, even these languages are not entirely dead. Evidence for Cumbric and Pictish remains in modern-day placenames such as the Scottish city Aberdeen and the English mountain Helvellyn. The vigesimal sheep-counting system traditionally used by upland farmers in the north of Britain is an oral remnant of Brythonic. Several hundred Gaulish words survive in modern French, including some very common words like aller, cheval, and petit. Some linguists attribute the "odd" pronunciation of French, distinct from that of other Romance languages, to the influence of Gaulish.

The modern Galician language is not Celtic, rather it is a Romance language closely related to Portuguese.

See

Itineraries

• Newfoundland's Trepassey and the Irish Loop

Museums of Celtic culture and history

• 1 Highland Village (Baile nan Gàidheal), Iona, Cape Breton Island, Nova Scotia, Canada. An outdoor, living-history about Gaels in Cape Breton. (updated Sep 2019)

• Hector ship, Pictou, Nova Scotia
• Quarantine station at Grosse Isle, Quebec
• 2 Tilting National Historic Site , Fogo Island and Change Islands, Newfoundland and Labrador. An historic village recognized for its distinctive Irish-Newfoundlander culture.

• 3 St Fagans National History Museum, Cardiff, Wales. An open-air museum of vernacular buildings from all parts of Wales rebuilt, stone by stone, in the grounds of St Fagans Castle. Also contains permanent inside exhibitions on Welsh social and cultural history. (updated Sep 2019)

Celtic Christianity sites

• 4 Glendalough, County Wicklow, Ireland, ☏ 353 404 45352, 353 404 45325. Daily 09:30-17:00 (18:00 mid-Mar till mid-Oct). A monastic settlement founded by Saint Kevin in the sixth century. Guided tours of the Monastic City are available in multiple languages all year round by advance booking. The Visitor Centre also holds Free Summer Lectures related to Irish heritage and history.  

Celtic festivals

• Festival Interceltique de Lorient (Gouelioù Etrekeltiek An Oriant) (Lorient, Brittany, France). First or second week of August. Probably the world's largest annual festival celebrating all things Celtic, from national costume, music and dance to the visual arts, artisanry, sports and cuisine. Invites and attracts participants from all the Celtic nations, and from many important Celtic diasporas around the world, though each year the focus is on one particular nation. (updated Mar 2020)

• National Eisteddfod of Wales (Eisteddfod Genedlaethol Cymru) (held in a different town or city of Wales each year). First week of August. Wales's national festival of literature, poetry and music with a competitive element. (updated Mar 2020)
• Celtic Colours Festival (Cape Breton, Nova Scotia, Canada). Early-to-mid-October. Spanning hundreds of events across dozens of towns, the music options at Celtic Colours are not solely Celtic but include folk and some Acadian Zydeco (Acadeco) and jazz, and an increasing amount of world music. (updated Sep 2019)
• Canada's Irish Festival (Miramichi, New Brunswick, Canada). Third weekend of July. Canada's longest-running Irish festival takes place with music, dancing, Irish arts and craft, and that most Canadian obsession – ancestry research! (updated Mar 2020)