The Brittonic, Brythonic or British Celtic languages form one of the two branches of the Insular Celtic language family; the other is Goidelic. The name Brythonic was derived by Welsh Celticist John Rhys from the Welsh word Brython, meaning Ancient Britons as opposed to an Anglo-Saxon or Gael.
The Celtic languages are a group of related languages descended from Proto-Celtic. They form a branch of the Indo-European language family. The term "Celtic" was first used to describe this language group by Edward Lhuyd in 1707, following Paul-Yves Pezron, who made the explicit link between the Celts described by classical writers and the Welsh and Breton languages.
The Celts are a collection of Indo-European peoples in parts of Europe and Anatolia identified by their use of the Celtic languages and other cultural similarities. Historic Celtic groups included the Gauls, Celtiberians, Gallaecians, Galatians, Britons, Gaels, and their offshoots. The relationship between ethnicity, language and culture in the Celtic world is unclear and controversial. In particular, there is dispute over the ways in which the Iron Age inhabitants of Britain and Ireland should be regarded as Celts.
The Goidelic or Gaelic languages form one of the two groups of Insular Celtic languages, the other being the Brittonic languages.
Pictish is the extinct language spoken by the Picts, the people of eastern and northern Scotland from Late Antiquity to the Early Middle Ages. Virtually no direct attestations of Pictish remain, short of a limited number of geographical and personal names found on monuments and the contemporary records in the area controlled by the kingdoms of the Picts, dating to the early medieval period. Such evidence, however, points to the language being an Insular Celtic language related to the Brittonic language spoken prior to Anglo-Saxon settlement in what is now southern Scotland, England, and Wales.
Insular Celtic languages are the group of Celtic languages of Great Britain, Ireland and Brittany.
Celtiberian or Northeastern Hispano-Celtic is an extinct Indo-European language of the Celtic branch spoken by the Celtiberians in an area of the Iberian Peninsula between the headwaters of the Douro, Tagus, Júcar and Turia rivers and the Ebro river. This language is directly attested in nearly 200 inscriptions dated to the 2nd and 1st centuries BC, mainly in Celtiberian script, a direct adaptation of the northeastern Iberian script, but also in the Latin alphabet. The longest extant Celtiberian inscriptions are those on three Botorrita plaques, bronze plaques from Botorrita near Zaragoza, dating to the early 1st century BC, labelled Botorrita I, III and IV. In the northwest was another Celtic language, Gallaecian, that was closely related to Celtiberian.
The Southwestern Brittonic languages are the Brittonic Celtic languages spoken in what is now South West England, and Armorica now in France, since the Early Middle Ages. During the period of their earliest attestation, the languages appear to be indistinguishable, but they gradually evolved into the languages Cornish, and Breton. Both languages evolved from the Common Brittonic formerly spoken across most of Britain and were thus related to the Welsh and Cumbric varieties spoken in Wales and Hen Ogledd, respectively. The older term Southwestern Brythonic languages is sometimes also used.
The Proto-Celtic language, also called Common Celtic, is the ancestral proto-language of all the known Celtic languages, and a descendant of the Proto-Indo-European language. It is not directly attested in writing, but has been partially reconstructed through the comparative method. Proto-Celtic is generally believed to have been spoken between 1300 and 800 BC, after which it began to evolve into individual Celtic languages. Proto-Celtic is usually associated with the Urnfield or Hallstatt archaeological cultures. Celtic languages share common features with Italic languages that are not found in other branches of Indo-European, suggesting the possibility that an earlier Italo-Celtic linguistic unity may have existed.
In historical linguistics, Italo-Celtic is a hypothetical grouping of the Italic and Celtic branches of the Indo-European language family on the basis of features shared by these two branches and no others. There is controversy about the causes of these similarities. They are usually considered to be innovations, likely to have developed after the breakup of the Proto-Indo-European language. It is also possible that some of these are not innovations, but shared conservative features, i.e. original Indo-European language features which have disappeared in all other language groups. What is commonly accepted is that the shared features may usefully be thought of as Italo-Celtic forms, as they are certainly shared by the two families and are almost certainly not coincidental.
The Continental Celtic languages is the now-extinct group of the Celtic languages that were spoken on the continent of Europe and in central Anatolia, as distinguished from the Insular Celtic languages of the British Isles and Brittany. Continental Celtic is a geographic, rather than linguistic, grouping of the ancient Celtic languages.
The Britons, also known as Celtic Britons or Ancient Britons, were the indigenous Celtic people who inhabited Great Britain from at least the British Iron Age and into the Middle Ages, at which point they diverged into the Welsh, Cornish and Bretons. They spoke the Common Brittonic language, the ancestor of the modern Brittonic languages.
The Celtic nations are a cultural area and collection of geographical regions in Western Europe and the North Atlantic Ocean where the Celtic languages and cultural traits have survived. The term nation is used in its original sense to mean a people who share a common identity and culture and are identified with a traditional territory.
The various names used since classical times for the people known today as the Celts are of disparate origins.
Celtic toponymy is the study of place names wholly or partially of Celtic origin. These names are found throughout continental Europe, Britain, Ireland, Anatolia and, latterly, through various other parts of the globe not originally occupied by Celts.
The Goidelic substrate hypothesis refers to the hypothesized language or languages spoken in Ireland before the Iron Age arrival of the Goidelic languages.
The Insular Celts are the speakers of the Insular Celtic languages, which comprise all the living Celtic languages as well as their precursors, which originated in Great Britain and Ireland. The term is mostly used in reference to the peoples of the British Iron Age prior to the Roman conquest, and their contemporaries in Ireland.
Common Brittonic, also known as Common Brythonic or Proto-Brittonic, was a Celtic language spoken in Britain and Brittany.
Gaulish was an ancient Celtic language that was spoken in parts of Continental Europe before and during the period of the Roman Empire. In the narrow sense, Gaulish was the language spoken by the Celtic inhabitants of Gaul. In a wider sense, it also comprises varieties of Celtic that were spoken across much of central Europe ("Noric"), parts of the Balkans, and Anatolia ("Galatian"), which are thought to have been closely related. The more divergent Lepontic of Northern Italy has also sometimes been subsumed under Gaulish.