These are the Ard Rí or High Kings of Ireland. It is a very long list and spans some 2,500 years of history, although it has to be said that most of the early kings listed are more the stuff of myth and legend. It should also be recognised that they are 'high kings' not 'kings' of Ireland; in general they were recognised as overlords of Ireland but were also kings of some specific kingdom within Ireland. Whereas in their own kingdoms they were kings, the extent of their authority over the rest of Ireland was often quite limited.
It begins with Eireamhón and Éibhear, the supposed sons of Milesius of Spain who set out from Galacia with their fleet and drove out the Tuatha-de-Danann from Ireland and made it their own.
The first truly historical high king is very probably Niall Naoighiallach or Niall of the Nine Hostages as he is known who who ruled in the period between 379 and 405 AD. The last high king was Ruaidhrí Ó Conchubhair otherwise known as Roderic or Rory O'Connor, who effectively stood down as high king when he recognised Henry II of England as his overlord in 1075.
The list is sometimes extended to include;
The list below gives the names of the kings in the original Gaeilge or Irish Gaelic.
The Legendary High Kings of Ireland
The Historical High Kings of Ireland