Insular Celts

The Insular Celts are the speakers of the Insular Celtic languages, which comprise all the living Celtic languages as well as their precursors, but 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. The term may also be used for the peoples of the modern Celtic nations.

According to older theories, the Insular Celtic languages spread throughout the islands in the course of the insular Iron Age. But this is now doubted by most scholars, who see the languages as already present, and possibly dominant, in the Bronze Age, and perhaps earlier. At some point the languages split into the two major groups, Goidelic in Ireland and Brittonic in Great Britain, corresponding to the population groups of the Goidels (Gaels) on one hand and the Britons and the Picts on the other. The extent to which these peoples ever formed a distinct ethnic group remains unclear. While there are early records of the Continental Celtic languages, allowing a comparatively confident reconstruction of Proto-Celtic, Insular Celtic languages become attested in connected texts only at the end of the Dark Ages, from around the 7th century AD, by which time they had become mutually incomprehensible.

In older theories, the arrival of Celts, defined as speakers of Celtic languages which derive from a Proto-Celtic language, roughly coincided with the beginning of the European Iron Age. In 1946 the Celtic scholar T. F. O'Rahilly published his influential model of the early history of Ireland which postulated four separate waves of Celtic invaders, spanning most of the Iron Age (700 to 100 BCE). However the archaeological evidence for these waves of invaders proved elusive. Later research indicated that the culture may have developed gradually and continuously between the Celts and the indigenous populations. Similarly in Ireland little archaeological evidence was found for large intrusive groups of Celtic immigrants, suggesting to archaeologists such as Colin Renfrew that the native late Bronze Age inhabitants gradually absorbed European Celtic influences and language.

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