The Earl of Tyrone is a title created three times in the Peerage of Ireland.
It was first created as part of the Tudor attempt to establish a uniform social structure in Ireland by converting the Gaelic kings and chiefs into hereditary nobles of the Kingdom of Ireland. Under brehon law, clans were effectively independent, and chose their chiefs from the members of a bloodline – normally, but not always, a close relative of the previous chief; the clan as a whole generally had a voice in the chief's decisions. Also, acknowledged sons of a clan member were members of the bloodline, even when not begotten in lawful marriage. The holder of a title, on the other hand, was subject to the Crown, but held his lands by hereditary right, which the Crown would help to enforce; the rest of the clan were usually now his tenants. Illegitimate sons had no right of succession under the new system unless expressly granted.
The title in the Peerage of Ireland was created again in 1673 for Richard Power, 6th Baron Power, the Anglo-Norman peer and Restoration politician, along with a large grant of land in County Waterford, at the other end of Ireland. He was also given the subordinate title of Viscount Decies; both titles became extinct upon the death of his younger son, the third earl, in 1704; he left an only daughter, Lady Katherine Power, but both titles descended by patent to male heirs only.
It was created a final time in 1746 for Marcus Beresford, 1st Viscount Tyrone, son-in-law of the last Power earl. His son was created Marquess of Waterford in 1789, and the title has since been a subsidiary title of the Waterford title.
The king and chief of the O'Neills of Tyrone, Conn Bacach O'Neill, went to Greenwich and submitted to Henry VIII of England and of Ireland in 1542; he renounced the style of "The O'Neill" and his independent rule. In exchange, he was created Earl of Tyrone, which was by the charter to descend to his illegitimate son Matthew or Ferdoragh O'Neill, who was also created Baron of Dungannon, which was always to be held by the heir to the Earldom; this was a substantive title, which gave Ferdoragh a seat in the Irish House of Lords, not a courtesy title. This adaptive process, known as "surrender and regrant", was taken up by other Irish clan chiefs.
This passed over Conn's legitimate sons; the eldest, Shane O'Neill, was only about twelve at the time. When he grew up, Shane (who is remembered as Séan an Diomais, or "Shane the Proud") drove his father out of Ulster, and was inaugurated The O'Neill (in Irish: Uí Neíll). There was civil strife among the Cenell Eoghain; Shane was victorious, Ferdoragh was killed, Conn was permanently driven out of Tyrone, and died in the Irish Pale in 1559, the area of Ireland directly governed by the English.
In English law, Ferdoragh's eldest son, Brian O'Neill, then succeeded to the Earldom; in practice he continued to be called Lord Dungannon. Queen Elizabeth I, newly come to the throne, proposed to recognize Shane as Earl, since he actually ruled Tyrone and was the eldest legitimate son; but the negotiations collapsed. Brian was killed in 1562, while still young and unmarried, by his cousin Turlough O'Neill, the tanist of his uncle Shane (and a grandson of the brother of Conn Bacagh, the first Earl). Shane died in June 1567, whereupon the English generally supported Brian's younger brother Hugh O'Neill against Turlough Linneach O'Neill. But Turlough was inaugurated The O'Neill Mor and as leader of the clan, was perceived to be the greater threat to English control of Ireland. In 1585, Hugh was recognized as Earl of Tyrone. In 1593, Turlough surrendered to him the position of "The O'Neill" to the Earl and retired.
Hugh O'Neill's career as unquestioned leader of the O'Neills became a series of quarrels with the English government: like many great feudal lords, he rebelled in the Nine Years' War, was proclaimed a traitor, and ultimately submitted to the Crown at the Treaty of Mellifont in 1603. Despite the Anglo-Spanish peace treaty of 1604, in 1607 O'Neill, his brother-in-law the Earl of Tyrconnell, and several of their followers fled to Europe, expecting the Spanish to invade Ireland with an army. He was found guilty of treason the year after this Flight of the Earls. The attainder was confirmed by the Parliament of Ireland in 1614; at which point the Earldom became forfeit under the common law.
Notwithstanding this attaintment, Earl Hugh, followed by his sons, continued to claim to be Earl of Tyrone, through its recognition by the Pope and the King of Spain, until the last legitimate grandson died unmarried, in 1692. Irish marriage practices at the time allowed for a political divorce, but all children were considered legitimate by the Irish: Hugh was married four times. Historians have stated that at this point the Irish title became extinct, as well as forfeit; however, that is by English law of descent. Gaelic law allowed for chiefships and property to descend through tanistry, and thus the descendants of Earl Hugh's brothers acted as The O'Neills of Tyrone, and called themselves Earl of Tyrone by Spanish grant, for the rest of the century. At that point, the chiefship and property transferred to the O'Neill of Tyrone existent back in Ireland through the descendants of Prince Shane O'Neill.
The Barony of Dungannon created for Matthew or Ferdoragh O'Neill was limited, by the terms of the patent, to his descendants who were heirs apparent to the Earldom of Tyrone. This provision would have meant that it acted like a courtesy title: when an Earl of Tyrone had an eldest son, or an eldest grandson by a deceased eldest son, that heir would be Baron Dungannon; when there was no heir apparent, the Barony of Dungannon lapsed until there was.
So when Matthew died, his son Brian became Baron Dungannon. However, when Conn Bacach died the next year, Brien was not recognized as Earl of Tyrone, but continued to be called Baron Dungannon until he was killed by Turlough Luineach O'Neill, Shane O'Neill's tanist.
His younger brother Hugh O'Neill was called Baron of Dungannon until 1585, when he received a charter confirming him as Earl of Tyrone. The same charter confirmed his son Hugh, the eldest son of his second wife, as Baron Dungannon; Earl Hugh's first marriage was invalid, and his children by that marriage illegitimate.
The following men were known as Baron Dungannon:
Since the younger Hugh O'Neill was attainted with father in 1608, the title is forfeit, and is now extinct. Young Hugh went to Rome with his father, and died there in the summer of 1609.
Earl Hugh and his family continued to lead the O'Neills of Tyrone from abroad; they also had the title of Earl of Tyrone recognized in Spain in the form of Conde de Tyrone. "Though no longer recognized in England, it was granted by Spanish kings to a line of O'Neills in rightful succession to the end of the seventeenth century".
By 1660, therefore, the Earldom of Tyrone was forfeit by English standards. Nonetheless, by Spanish and Irish standards the collateral O'Neill descendants of Mathew "Ferdocha" O'Neill, were allowed to use the title in Spain until 1692. At that point, it went to the senior member of the descendants of Prince Shane O'Neill, the half brother of Mathew "Ferdocha" O'Neill.
By this point, the claim to the Earldom of Tyrone became intertwined both with the position of the O'Neill of Tyrone and the wider position of chief of all the O'Neills of Ulster. Not all the claimants to the Gaelic offices claimed the Earldom: the descendants of Shane the Proud were inaugurated as the O'Neill by the ancient ritual, by which the O'Hagan put golden shoes on their feet on May Eve, without calling themselves Earls. In fact, Don Constantino or Conn McShane O'Neill went to Spain in 1681 to claim the chiefship and regiment from the King of Spain, upon the death of his cousin, Don Bernardo. He carried proofs of his senior descent from Prince Shane O'Neill, but was late to arrive. In the meantime, the King granted the estates to the minor Eugene O'Neill. This Conn went back to Ireland and was a senior member of the Jacobite O'Neills in the Williamite War.
The leadership of the O'Neills as a whole had usually been held by the O'Neills of Tyrone; but their distant cousins the O'Neills of Clanaboy or Clandeboye in Antrim had also sometimes held it, most recently Art mac Aodha O'Neill, from 1509 to 1514, when the first Earl was young. They, like the O'Neills of Tyrone, spent much of the seventeenth century fighting for the Catholic powers; in 1740 they relocated permanently to Portugal.
Don Jorge O'Neill of Clanaboy and Lisbon submitted his pedigree to the Ulster office of Heralds; in 1895 the genealogy and arms were confirmed. 1903 he received a patent from Sir Henry Farnham Burke, Somerset Herald, acknowledging that he had proved his royal descent from the Kings of Ireland, and his collateral descent from Hugh O'Neill, and thus was the representative of the Earldom and the senior member of the Royal family of O'Neill of Ulster. Although collateral descent from the grantee does not confer a peerage, he assumed the style of Conde de Tyrone, but his descendants use the title Prince of Clandeboye. Queen Victoria's recognition was followed by those of the Pope, the kings of Spain and Portugal, and the Republic of Ireland in 1945 as the Prince of Clandeboye.
with subsidiaries Viscount Decies (1673) and Baron Power (1535)