The term Kingship of Tara was a title of authority in ancient Ireland. The position was considered to be of eminent authority in medieval Irish literature and mythology, although national kingship was never a historical reality in early Ireland. The term also represented a prehistoric and mythical ideal of sacred kingship in Ireland. Holding the title King of Tara invested the incumbent with a powerful status. Many Irish High Kings were simultaneously Kings of Tara. The title emerged in the ninth and tenth centuries. In later times,[when?] actual claimants to this title used their position to promote themselves in status and fact to the High Kingship. Prior to this, various branches of the Uí Néill dynasty appear to have used it to denote overlordship of their kindred and realms.
The following is a list of those accorded the title (or at least believed to be seated) in the Irish annals—the kings and legends. The dates and names of the early kings are uncertain and are often highly suspect. Several may be doubles of others, while composite characters may be entirely fictitious. Some may also be assigned to the wrong prehistoric kindred.
^These five early kings belong to the same family in the sources, but their origin is variously asserted, and in any case they belong mostly to the realm of mythology. They were adopted into the medieval genealogies of the later Dál Cuinn (Connachta and Uí Néill), but are mostly entangled with the Érainn and the Ulaid in Irish legend.
^This kindred appear to have early divided themselves into quite discreet septs, and somehow spread themselves in a long belt from Munster through Ulster across to southwestern Scotland with no clear point of radiation. Their other principal sept are believed to have been the famous Ulaid, early rulers of the north of Ireland from Emain Macha in Ulster (the kingship of which may actually have stood above the Tara kingship for some centuries).
^A well-known problem and peculiarity of the Érainn and Dáirine kings is that several appear to have numerous doubles spread out across the Irish mytho-historical landscape, who turn up not only in their own pedigrees but in those of other kindreds as well. In the case of Conaire, he may only be split in two, but the following Dáire and Lugaid each appear to have numerous doubles.
^Scholars have been divided as to whether the Laigin should precede or follow the Érainn. Early legends appear to recall ancient wars fought between the two for control of Tara, Brega and the Midlands. At some point in Irish prehistory the Laigin and related kindreds (Gáileóin and Domnainn) are believed to have arrived from Britain or Gaul to settle in Leinster, to which they gave their name, and from which they would radiate to early rule in Connacht and elsewhere. They would later lose control of the Tara region to the expanding Uí Néill.
^The Dál Cuinn are that kindred whom scholars distinguish to be the immediate ancestors of Conn of the Hundred Battles and his descendants down to Eochaid Mugmedón, after whom they split into the historical Connachta and Uí Néill. Believed to originate among or be identical to the prehistoric groups of Féni, meaning 'warriors', their ultimate origins have been enthusiastically speculated upon but are basically unknown. As a proto-dynasty, they are earliest found in the province of Connacht, to which the later Connachta gave their name, and may be more or less identical with the Connachta known from the Ulster Cycle. T. F. O'Rahilly asserted that they brought the Gaelic language to Ireland from the Continent in relatively late prehistoric times, but this idea has not proven popular with later generations of scholars. The kindred appear to have radiated from within Connacht to dominate that province and then outwards to western Ulster and the Midlands, after which they would virtually monopolize the Tara kingship for several centuries. In some works, the term Dál Cuinn is replaced by the more convenient Connachta and the latter adopts its meaning in addition to its history.
^Supposed son of Feradach Finnfechtnach, and alleged father of Tuathal Techtmar. An actual link between the two dynasties cannot be demonstrated (except in the realm of the medieval genealogies).