|Kingdom of West Breifne|
|Bréifne Ua Ruairc (Irish)|
A map of 1450 Ireland showing Breifne O'Rourke
|-||Split from Breifne||1256|
The Kingdom of West Breifne (Irish Breifne Ua Ruairc) was an historic kingdom of Ireland that existed from 1256 to 1605, located in the area that is now County Leitrim. It took its present boundaries in 1583 when West Breifne was shired and renamed Leitrim, after the village of Leitrim, which was an O'Rourke stronghold. The kingdom came into existence after a battle between the O'Rourke clans and the O'Reilly's caused the break up of the older Kingdom of Breifne and led to the formation of East Breifne and West Breifne. The Kingdom was ruled by the various O'Rourke clans and lasted until the early 17th century, when the Kingdom of England confiscated their lands.
In 1172, Tighearnán Ua Ruairc, the longtime Lord of Breifne and Conmaice, was betrayed and killed at Tlachtgha during negotiations with Hugh de Lacy, Lord of Meath. Tighearnán was beheaded, and his head and body was conveyed to the Anglo-Normans in Dublin, where it was put on display. The assassination of Tighernán caused a war of succession in Breifne and for the next hundred years there would be no long standing King of Breifne, as rival O'Rourke clans fought for the kingship. This time of turbulence in the kingdom caused a great rift between the various O'Rourke clans, with regular fighting between rival members. This period of instability prompted the O'Reillys in the east of the kingdom to launch a campaign against Connacht and the O'Rourke clans. In 1256 a battle was fought between Connacht and the O'Rourke clans against the O'Reilly. Despite ending in an O'Rourke victory, they had lost complete control over the eastern half of their kingdom, thus dividing Breifne into East Breifne (O'Reilly) and West Breifne (O'Rourke).
Conflict with Connacht
After the battle, Conchobar O'Ruairc, King of West Breifne, came into conflict with Aedh O'Conor, son of Felim O'Conor, the King of Connacht. According to the Annals of Connacht, the two men "had been good comrades till now". Shortly after this dispute, Conchobar made peace with The Galls without the permission of the king of Connacht, prompting Aedh O'Conor to launch raids on West Breifne. In 1257, after a brief war, Conchobar submitted to O'Conor and signed a peace treaty offering O'Conor any lands of his choice in Breifne. O'Conor obtained the stone-castle on Cherry Island in Garadice Lough and put a garrison into it. Later that year, Conchobar violated the terms of the treaty and forced O'Conor's garrison out of the castle before razing it. Due to this act of betrayal, Aedh O'Conor elected Sitric O'Ruairc to replace Conchobar as king of West Breifne, however Sitric was soon killed by Domnall, Conchobar's son, to avenge his fathers dispossession. This led to Domnall's arrest and imprisonment and Aedh O'Conor resumed raids on West Breifne.
In 1258, with the war against Connacht still ongoing, Conchobar was betrayed and killed by his own men. After his fathers death, Domnall was released from prison and instated as king of West Breifne. However, shortly after his appointment as king, Domnall killed Magrath Mac Tiernan, chieftain of Tellach-Dunchada, which was a clan that held land within Breifne. As a result of this killing, Domnall was deposed as king by the major clans of West Breifne, including Tellach-Dunchada, who executed Domnall's brother Cathal in retaliation. 
After Domnall was deposed, Art O'Ruairc was instated as king, but in 1259, he was taken prisoner by Connacht. Aedh O'Conor then met with Domnall and after peace between the two kingdoms was agreed, kingship was returned to Domnall. However, this peace was to be short lived, in 1260 the Tellach-Dunchada killed Domnall and in 1261 Art O'Ruairc escaped from imprisonment and was made king by the chieftains of Breifne upon his return. An attempt by Connacht to deposed Art O'Ruairc in 1261 failed when their army was defeated at Drumlahan.
The conflict between Connacht and West Breifne ended in 1266, when Aedh O'Conor, now King of Connacht, launched a successful invasion of West Breifne and deposed Art O'Ruairc, instating Conchobar buide, son of King Amlaíb (1257-1258), as the new king. Aedh O'Conor also took hostages from all the major clans of the kingdom. 
Wars of Succession
West Breifne continued to see disputes over kingship, with persistent battles between rival factions. There were three main branches of royalty, O'Rourkes of Dromahair, O'Rourkes of Carha and O'Rourkes of Cloncorick, as well as several others. The rivalry between these branches continued until the 1560s when they united to fight against English intruders who were attempting to colonise the area. The most significant of the rivalries was between the O'Rourkes of Dromahair, the main line of the Kings, and the O'Rourkes of Carnha. This rivalry would see the kingdom split between "East Breifne O'Rourke" (Dromahair) and was "West Breifne O'Rourke" (Carnha) at several different times, the first from 1419 to 1424, following the death of King Aedh buidhe. Aedh's brother, Tadhg, was chosen to succeed his brother as King, however in southern Leitrim, Art O'Rourke, son of King Tadgh na gcoar (1352-1376), was elected King by his supporters. The division lasted for five years until Art O'Rourke submitted kingship to Tadhg in 1424.
The second split occurred after King Tadhg's death in 1435. King Tadhg was to be succeeded by his brother Donnchadh bacagh. However, Art O'Rourke's brother, Lochlainn Ó Ruairc, was declared "King of East Breifne O'Rourke" and the kingdom was again divided. This divide would last for 23 years until 1458, when Lochlainn Ó Ruairc was defeated by the Maguires of Fermanagh, the kingship of East Breifne O'Rourke was dissolved and Tigernán óg became King of a united West Breifne.
Following the death of King Tigernán óg in 1468, kingship was again in dispute, this time between Domnall, Tigernán óg's brother, and Donnchadh losc, son of King Tigernán mór (1376-1418). Domnall was supported by the O'Rourkes of Dromahair and Ruadh O'Donnell, the Lord of Tír Chonaill. Donnchadh losc received support from the O'Rourkes of Carha as well as the people of Carbury and the Clann-Donough. In 1470, Domnall and O'Donnell led an army to "Cruachan", the traditional inauguration site of kings, in an attempt to inaugurate Domnall, however they were stopped at Ballyconnell by the O'Reilly and the English. This dispute caused infighting within West Breifne and left a deepened rivalry between the O'Rourkes of Dromahair and the O'Rourkes of Carha. The dispute ended in a victory for the O'Rourkes of Carha and the crowning of King Feidhlimidh in 1476.
Nine Years War
During the Anglo-Spanish War (1585-1604), Lord Brian na Múrtha Ó Ruairc, who was unhappy with English interference in his territories, assisted at least eighty survivors of the Spanish Armada shipwreck off the Sligo coast to depart the country in the winter of 1588. Among the survivors was Captain Francisco de Cuellar, who kept a detailed account of the events and was hosted in Ó Ruairc's castle at Lough Gill. In peace talks in 1589, Brian Ó Ruairc did accept the terms of a crown tribute that had been agreed by his grandfather, but resisted the composition terms of 1585 and refused to allow the formation of a crown administration in the new County Leitrim. This made him an enemy of the English and in the spring of 1590, Sir Richard Bingham led forces into West Breifne and occupied the territory, forcing Ó Ruairc to flee. He fled to Scotland but was later extradited to England and kept at the Tower of London. He was put on trial and was asked to pledge to the crown and denounce his Catholic faith, he refused and was hanged for treason in 1591.
When news of Brian na Múrtha's death reached Breifne, Brian Og na Samhthach, his son, succeeded him as King. The O'Rourke clans had united in the 1560s to fight off English intruders and West Breifne forces were part of the Alliance of Irish clans, led by Hugh O'Neill, during the Nine Years' War. In 1599, Brain Og's forces fought alongside those of "Red" Hugh O'Donnell at the Battle of Curlew Pass.
After defeat in the Nine Years' War, many O'Rourke nobles, as well as O'Reilly's from neighbouring East Breifne, left Ireland for mainland Europe. The clans throughout Ireland went into a steady decline during this period. In 1605 King Tadhg mac Briain na Murtha died aged 28, some suspect he may have been poisoned. Following the death of King Tadhg, his sons Brian and Aedh were declared illegitimate by the English which ultimately caused them to lose their claim to their father's inheritance, effectively ending West Breifne.
Kings (Lords) of Breifne O'Rourke
|Conchobar||1250-1257||son of Tigernán son of Domnall||Deposed|
|Sitric||1257||son of Ualgarg son of Cathal||Elected and killed|
|Amlaíb||1257-1258||son of Art son of Domnall son of Fergal|
|Domnall O'Ruairc||1258||son of Conchobar son of Tigernán||Deposed|
|Art O'Ruairc||1258-1259||son of Cathal riabach son of Donnchadh||Deposed|
|Domnall O'Ruairc||1259-1260||son of Conchobar son of Tigernán||Killed|
|Art bec||1260||son of Art son of Domnall son of Fergal|
|Art O'Ruairc||1261-1266||son of Cathal riabach son of Donnchadh||Deposed|
|Conchobar buide||1266-1273||son of Amlaíb son of Art|
|Tigernán||1273-1274||son of Aedh son of Ualgarg son of Cathal|
|Art O'Ruairc||1275||son of Cathal riabach son of Donnchadh|
|Amlaíb O'Ruairc||1275-1307||son of Art son of Cathal riabach|
|Domnall carrach||1307-1311||son of Amlaíb son of Art|
|Ualgarg mór||1316-1346||son of Domnall carrach||Killed †|
|Flaithbheartach||1346-1349||son of Domnall carrach||Deposed|
|Aodh bán||1349-1352||son of Ualgarg mór son of Domnall||Killed †|
|Flaithbheartach||1352||son of Domnall carrach|
|Tadgh na gcoar||1352-1376||son of Ualgarg mór son of Domnall carrach|
|Tigernán mór||1376-1418||son of Ualgarg mór son of Domnall carrach|
|Aodh buidhe||1418-1419||son of Tigernán mór|
|Tadhg O'Rourke||1419-1424||son of Tigernán mór||Elected (Kingship Disputed)[n 1]|
|Art O'Rourke||1419-1424||son of Tadhg na gcoar||Elected (Kingship Disputed)[n 1]|
|Tadhg O'Rourke||1424-1435||son of Tigernán mór|
|Lochlann O'Rourke||1435-1458||son of Tadhg na gcoar||King of East Breifne O'Rourke[n 2]|
|Donnchadh bacagh||1435-1445||son of Tigernán mór||King of West Breifne O'Rourke[n 2]|
|Donnchadh||1445-1449||son of Tigernán óg son of Tigernán mór||King of West Breifne O'Rourke[n 2]|
|Tigernán óg||1449-1468||son of Tadhg son of Tigernán mór|
|Domnall||1468-1476||son of Tadhg son of Tigernán mór||Kingship disputed[n 3]|
|Donnchadh losc||1468-1476||son of Tigernán mór son of Ualgarg mór||Kingship disputed[n 3]|
|Feidhlimidh mac Donnchadha||1476-1500||son of Donnchadh son of Tigernán óg|
|Eóghan||1500-1528||son of Tigernán óg son of Tadhg|
|Feidhlimidh||1528-1536||son of Feidhlimidh son of Donnchadh|
|Brian Ballach||1536-1559||son of Eóghan son of Tigernán óg|
|Tadhg||1559-1560||son of Brian ballach|
|Brian Ballach||1560-1562||son of Eóghan son of Tigernán óg|
|Aodh Gallda||1562-1564||son of Brian ballach|
|Aodh Buidhe||1564-1566||son of Brian ballach|
|Brian na Murtha||1566-1591||son of Brian ballach||Executed[n 4]|
|Brian Og na Samhthach||1591-1600||son Brian na Murtha son of Briain Bhalliagh|
|Tadhg mac Briain na Murtha||1600-1605||son of Brian na múrtha||[n 5]|
- Following the death of King Aedh buidhe in 1419, the O'Rourkes in Northern County Leitrim elected Tadhg O'Rourke, Aedh buidhe's brother, as King. In Southern Leitrim, Art O'Rourke, son of King Tadgh na gcoar (1352-1376), was elected King by his supporters. The Kingdom divided into "East Breifne O'Rourke" and "West Breifne O'Rourke" for several years until 1424, when Art O'Rourke submitted kingship to Tadhg O'Rourke.
- Following the death of King Tadhg O'Rourke in 1435, kingship was again in dispute between East and West. The Kingdom of West Breifne was divided between East and West for 23 years until 1458, when East Breifne O'Rourke were defeated and their kingdom was dissolved.
- Following the death of King Tigernán óg in 1468, kingship was again in dispute, this time between Domnall, Tigernán óg's brother who was supported by the O'Rourkes of Dromahair (the main line), and Donnchadh losc, son of King Tigernán mór (1376-1418) who was supported by fierce rivals of the main line, the O'Rourkes of Carha. This dispute caused infighting within West Breifne and left a deepened rivalry between the O'Rourkes of Dromahair and the O'Rourkes of Carha. The dispute ended in a victory for the O'Rourkes of Carha and the crowing of King Feidhlimidh in 1476.
- Hanged by the Kingdom of England in London for treason against the Queen's Law in 1591.
- Suspected assassination by poison
- Ancestry.com - Kingdom of Bréifne
- O'Reilly Kingdom of Breffni, clanoreilly.com
- Ancestry.com, O'Rourke excerpts from the Annals of the Four Masters
- Annals of Connacht - 1258
- Annals of Connacht - 1259
- Annals of Connacht - 1260
- Annals of Connacht - 1266
- O'Rourkes of Carrigallen
- O'Rourkes of Carha
- UCC, Captain Cuellar's Adventures in Connacht and Ulster
- Ancestry.com, Brian na Murtha
- Brian na Murtha Trial
- O'Rourke Clan History, orourkeclans.com
- O'Rourkes of Dromahair
- List of Breifne Kings