O'Neill dynasty in the context of "Tír Eoghain"

County Tyrone (/tɪˈroʊn/; from Irish Tír Eoghain, meaning 'land of Eoghan' [tʲiːɾʲ ˈoːnʲ]) is one of the six counties of Northern Ireland, one of the nine counties of Ulster and one of the thirty-two traditional counties of Ireland. Its county town is Omagh.

Adjoined to the south-west shore of Lough Neagh, the county covers an area of 1,261 square miles (3,266 km), making it the largest of Northern Ireland's six counties by size, and the second largest county in Ulster after Donegal. With a population of 188,383 as of the 2021 census, Tyrone is the 5th most populous county in both Northern Ireland and Ulster, and the 11th most populous county on the island of Ireland. The county derives its name and general geographic location from Tír Eoghain, a Gaelic kingdom under the O'Neill dynasty which existed until the 17th century.

On 14 September [O.S. 4 September] 1607, Irish earls Hugh O'Neill, Earl of Tyrone, and Rory O'Donnell, 1st Earl of Tyrconnell, permanently departed Rathmullan in Ireland for mainland Europe, accompanied by their extended families, retinue, followers and fellow nobility, numbering about 100 people. The earls were patriarchs of the two most powerful clans in Ulster—the O'Neill and O'Donnell clans—and their permanent exile is seen to symbolise the end of Gaelic Irish society. This event is known as the Flight of the Earls (Irish: Imeacht na nIarlaí).

Both earls fought against the English Crown in the Nine Years' War (1593–1603), which ended with their surrender. The newly crowned James VI and I granted the earls generous peace terms which allowed them to retain their lands and titles. Many courtiers were unsatisfied with the king's leniency, and hostility towards the earls from British officials gradually increased over time. The implementation of English law in Ireland led to financial difficulties for both earls as well as a major land rights dispute between Tyrone and his vassal Donnell Ballagh O'Cahan, which was weaponised by officials such as Arthur Chichester, John Davies, and George Montgomery.

Hugh O'Neill, Earl of Tyrone (Irish: Aodh Mór Ó Néill; c. 1550 – 10 July [N.S. 20 July] 1616) was an Irish lord and key figure of the Nine Years' War. Known as the "Great Earl", he led the confederacy of Irish lords against the English Crown's conquest of Ireland during the Elizabethan era.

He was born into the O'Neill clan, Tír Eoghain's ruling noble family, during a violent succession conflict which saw his father assassinated. At the age of eight he was relocated to the Pale where he was raised by an English family. Although the Crown hoped to mold him into a puppet ruler sympathetic to the English government, by the 1570s he had built a strong network of both English and Irish contacts which he utilised for his pursuit of political power, eventually becoming one of the richest and most powerful lords in Ireland.

Owen Roe O'Neill (Irish: Eoghan Ruadh Ó Néill; c. 1585 – 6 November 1649) was a Gaelic Irish soldier and one of the most famous of the O'Neill dynasty of Ulster. O'Neill left Ireland at a young age and spent most of his life as a mercenary in the Spanish Army serving against the Dutch in Flanders during the Eighty Years' War. After the Irish Rebellion of 1641, O'Neill returned and took command of the Irish Confederate Ulster Army. He is known for his victory at the Battle of Benburb in 1646.

O'Neill's later years were marked by infighting amongst the Confederates, and in 1647 he led his army to seize power in the capital of Kilkenny. His troops clashed with rival forces of the Confederacy, leading to O'Neill forming a temporary alliance with Charles Coote's English Parliamentary forces in Ulster. He initially rejected a treaty of alliance between the Confederates and the Irish Royalists, but faced with the Cromwellian invasion he changed his mind. O'Neill died shortly after agreeing to an alliance with the 1st Marquess of Ormond, the Lord Lieutenant of Ireland. The agreement included the promise of an Earldom, but O'Neill died on Tuesday, 6 November 1649.