Ancient Greeks knew the Celts as Keltai and later Galatai, both probably deriving from Celtic tribal names; the Latin equivalents were Celtae and Gallus. The Celtic (or Gaelic) languages belong to the wider Indo-European family, related to Greek, Latin, German, and English.
Origin of the Celts in Ireland
Earlier historiography held that Celts invaded Ireland from the continent sometime in the first millennium BC. More recent research suggests the introduction of Celtic culture and language was gradual rather than a single invasion. Either way, Celtic language and culture were well established in Ireland and Britain before 500 BC.
Celtic Kingdoms
Celtic tribes in Ireland established several kingdoms. One of the earliest in what’s now Northern Ireland was the Volunti, or Ulaid - mentioned in Ptolemy’s 2nd century AD Geographia, with a capital likely at Navan Fort (Eamhain Mhacha), County Armagh - well worth a visit today, with a real visitor centre on site. At their peak, the Ulaid’s territory stretched south to the River Boyne and west to County Leitrim. Navan Fort was destroyed in the 4th century AD, ending the kingdom.
Other early Irish kingdoms included the Erdini in County Fermanagh and the Robogdii in County Antrim and Londonderry.
Dalriada is perhaps the best-known Celtic kingdom, originating in Antrim and reaching, at its 6th- and 7th-century height, across south-western Scotland as well as County Antrim. It disappeared by the time of the Viking invasions, but is remembered above all for its connection to Saint Columba, who brought Christianity to northern Britain - the Book of Kells may well have been produced by Dalriadan monks.
Celtic Culture
Celtic society was organised tribally, led by a king, and divided broadly into three classes: the warrior aristocracy, an intellectual class of druids and poets, and everyone else. There’s both literary and archaeological evidence that some women held real authority and, in some cases, fought as warriors. Warfare was common, with soldiers carrying long swords and round or hexagonal shields. Trade moved along an established network of roads connecting the main tribal territories. Clothing included long-sleeved shirts and trousers, which the Romans called braccae.
