Clan History


Clan Origins and History

The O'Crowley Clan finds its origins in the Sil Murray, the group of clans issued and lead by the O'Connors kings of Connacht, descending from Murray (Muredagh Mullethan) king of Connacht 695-701. It is an off shot of the MacDermots Prince of Moylurg per the genealogies recorded in the Book of Munster, O'Clerys’ genealogies, and MacFirbis.

Tadhg Mor King of Connacht 923-956

his son, Maolrunaidh Mor Prince of Moylurg 956

his son, Murthough Prince of Moylurg

his son, Tadhg Prince of Moylurg

his son, Maolrunaidh Prince of Moylurg, died 1080

his son, Tadgh Mor Prince of Moylurg, 1120-1124

his son, Dermot (from whom the MacDermot line) Prince of Moylurg, 1124-1159

his son, Connor MacDermot Prince of Moylurg, 1186-1197

his son, Dermot MacDermot Prince of Moylurg, 1215-1218, hostage to King John in 1214, styled "Chruadh Laoich" or hard warrior returns to Moylurg in 1215 to assume the Princeship

his son, Donagh MacDermott O'Crowley, Prince of Moylurg, killed by Maurice Fitz Gerald in 1214

his son, Meicraith O'Crowley

his son, Dermot O'Crowley

The line of Donogh MacDermot O'Crowley excluded from main MacDermot Princely line will not get access to the title of Prince. However, in accordance to The MacDermot function as Seneschal to The O'Connor the O’Crowleys became warrior knights.

Establishment in Munster

In the mid 11th century the O’Briens ousted the MacCarthys kings of Munster from the plains of Tipperrary and their capital of Cashel. The MacCarthys moved south displacing local existing clans such as the O’Mahonys, O’Driscolls. The struggle for the supremacy of Munster continued in the 12th and 13th centuries. The High King O’Connor had been the initiator of the treaty of Glanmire in 1118 between the O’Briens and the MacCarthys confirming the partition of Munster into two realms, Thomond under The O’Brien and Desmond under The MacCarthy.

Again in the late 13th century King O’Connor of Connacht gets involved into the Munster affairs as an ally to The MacCarthy Mor. It must be a result of this alliance with The MacCarthy Mor and these events that in the mid 13th century O'Connor sends help to crush a rebellious branch of the MacCarthys and the O'Mahonys in Cork. In 1283 Ragnall O'Crowley is found being slained by Owen MacCarthy the rebel.  The Annals of Inisfallen state that MacCarthy Mor caused the people of Kilshallow to find refuge in other areas of Cork and subsequently caused great migrations notably into Kilshallow. It may be the result of these migrations that the O'Crowleys established themselves with a complete change of land ownership. During this period there are other examples in Ireland of aristocratic warrior families resettling from their original habitat, such as for example the MacQuillan or the O’Haras moving from Connacht into Ulster.

In 1295 Dermot and Conogher O'Crowley are found guilty of murder against Normans and are "hang, no chattels" in the City of Cork.

The living tradition recorded by Windele in the 19th century and earlier in the 17th century are that Dermot O'Crowley married the daughter of Cian O'Coughlan Lord of Kilshallow and thus acquired a hundred ploughlands passed to him in the mountainous and woody area of Kilshallow in Carbery, County of Cork. Worth noting the early seats of the O'Crowleys in Carbery as their name suggest are the townlands of Cahir O'Crowley north of the Bandon River, and Curragh O'Crowley to the south of the Bandon River in Phale. Phale is of particular interest since it was the first establishment of the MacCarthy's in Carbery, this may confirm an early alliance between the two families.

From 1283 the O'Crowleys grow and prosper in Carberry, where the Kilshallow lands are, offering their services as professional warriors of noble rank to the MacCarthy Reagh, Prince of Carbery, and The MacCarthy Mor. They became a leading clan in West Cork.By the 16th century the clan expanded out of Kilshallow lands, situated between Dunmanway and Bandon north of the Bandon River and both side of its tributary the Blackwater River. The Chief of the clan was a recognised Ard Tiarna or High Lord under the MacCarthy Reagh, a similar status to The O'Donovan, The O'Driscoll and The O'Mahony Carbery and Finn, the only free holders in Carbery with other MacCarthys septs. The O'Crowley Clan expansion will include the Parish of Kilnagross, lands in Kilmaloda, Ross Carbery, Dunishead, and further north in West Muskerry where a branch issued from Fyneen, Chief of his Name established itself around 1550 as warriors and officers to the Maccarthy Muskerry. As professional warriors the O'Crowley also provided constables and officers to The MacCarthy Reagh and The MacCarthy Muskerry.

The genealogy of the chiefs of the clan is as follow per the Book of Munster, O'Cruoly genealogie, O'Dineen, MacFirbis, O’Casey

Dermot O'Crowley


his son, Ruadhri


his son, Aodh


his son, Lochlainn Mor


his son, Raghnall


his son, Conor


his son, David

Records for the 14th century are almost inexistant. In 1449 The MacCarthy Reagh conqueers the all-important castle of Kilbrittain and associated lands from the de Courcy. Kilbrittain is major fortress at the time credited to have 9 flanking towers in addition to the keep. The O’Crowley must have participated to this feat of arms, and it may account for the establishment of the O’Crowley Og sept in the area acting as a military force. From that time The MacCarthy Reaghelected residence at Kilbrittain castle.

The first historical record in the 15th century is that of Auliffe O'Crowley Chief of his name and Lord of Kilshallow. He petitioned and persuaded the bishop of Ross to have a separate parish erected in Kilnagross on account of O'Crowley settlements, this was latter confirmed in 1493 by the Pope. Auliffe also sworn allegiance to the MacCarthy Reagh, Prince of Carbery in 1484 along with the other independent Lords of Carbery, O'Mahony, O'Driscoll, O'Donovan. MacCarthy Reagh had been encourgaged by Henry VII of England to receive such homage on his behalf and in return recognise the clan Chiefs as Lord of their lands.

The 15th and 16th centuries are a time of intense militarisation of Munster, the Irish Chiefs recovering some of their formerly lost territories to the Normans. The de Barry, Barrett and de Courcy lordships are reduced to areas along the coast of West Cork, some other Norman Lordships are entirely disappearing such as the Arundel. But most importantly is the struggle between the MacCarthys and the Fitzgerald Earl of Desmond. In 1520 The MacCarthy of Muskerry and The MacCarthy of Carbery form an alliance under The MacCarthy Mor and imposed a crushing defeat to the Fitzgerald of Desmond and his allies at Mourne Abbey.

Expansion outside Kilshalow

As analysis demonstrates the O’Crowleys lived under Gaelic or Brehon law, and thus aside from the Ard Tiarna (Chief of the clan) reserved Demesne (townlands of Kilmaloda, Ahakeera, Shanlaragh, Curraghdrinagh, Toom) representing about 25 % of the Kilshallow Lordship, the lands were redistributed at every Chief election sharing a common pattern with West Cork clans. The Ard Tiarna demesne was entirely established in the Parish of Fanllobbus. Also in Kilshallow another sept, O’Crowley na Madery was a cohesive hereditary sub Lordship of Tiarna rank in the Parish of Kinneigh.

The lands were redistributed amongst the clan families with preference given to the Chief relatives, typically the Tanaiste (designated heir) share would represent another 15%, the Chief’s brothers having a share from 5 to 10 %, other families would have as low as 1% of the clan lordship. This continuous process of land reallocation every 20 or 30 years combined with an increase of population, gradually and slowly reduced the other O’Crowley families, though co relatives to the Chief, to smaller land holding with a necessary expansion outside of Kilshallow.

The intense militarisation of life required professional warriors, as a result the O’Crowleys expended outside of Kilshallow with several establishments outside of the original Lordship, some quite significant with a recognised Sept Chief (Tiarna), others as just branch settlements but all usually in a cohesive manner and in Carbery. These establishments outside of Kilshallow but in Carbery sustained the connection with the Ard Tiarna of Kilshallow and will provide avenues for expansion as the clan population increased. Around 1550, altogether the lands belonging to the O’Crowleys comprising Kilshallow and other townlands represented approximately 12,000.  A yeoman or a Gaelic soldier was to hold between 60 and 120 acres, this appear to be consistent with number of O’Crowleys mentioned in the Government Pardons (Fiants), about 90. Per English standards a manor was between 1200 to 1800 acres. This also has some consistency with the eight historically recorded branch Chieftains which would each have some type of establishment similar as a function to the an English manor.

A notable feature particular to the O’Crowleys but also shared with other professional warrior clans such as the MacSweeneys, is the professional journey of individuals who would take service far from their home stead to serve paramount Lords. For example, in 1573 Fyneen O’Crowley owner of Dromgarrif in Kilnagross is constable to the MacCarthy Muskerry in Blarney. Another example is Teige mcDermot of Phale who prior to 1601 is in service to the MacCarthys of Phale. When both Fyneen and Teige would become the Ard Tiarna (Chief of the clan) they would move to Kilshallow and occupy the reserved Demesne for the Ard Tiarna with O’Crowley castle as their main residence.

O’Crowley Septs outside Kilshallow of Tiarna (Lord and Gentleman) rank ; - O’Crowley Og in Skeaff, and Kilnagross - O’Crowley Kippagh, Kippagh - O’Crowley of the Monteen, alias Mac y Valirty - O’Crowley MacFyneen, Kilnagross

Septs with out Tiarna rank (Gentleman); - O’Crowley Reagh, Ballinacarriga, Phale - O’Crowley Buy, Dromfeagh, Kinneigh - O’Crowley Baccagh, Tooreen, Caheragh, Ross Carbery - O’Crowley ny Gawine, Maraha

At the end of the 15th century a return of forces of Irish Chieftains states that The O'Crowley (probably Auliffe) maintains a private force of 8 horsemen and 60 kerns (foot warriors). Clans which specialised into specific trade had established schools. With their profession at arms the O’Crowleys must have had their “combat school” similar to the other professional warrior clans such as the MacSweeneys who were gallowglasses. The difference was the O’Crowley had a very strong blood ethos and only allowed O’Crowleys to be schooled, in all probability in O’Crowley Castle compound.

The genealogy of main septs stemming from David O'Crowley Chief circa 1420 is the following, it is the Ard Tiarna or Chiefly line and its collaterals;

David  Ard Tiarna circa 1450
   I--Teige Mor, Ard Tiarna circa 1520, at the battle of MourneAbbey
   I      I    
   I      I--Teige Og,=è O'Crowley Og Sept
   I             I   
   I             I-- Fyneen, of Drumgarrif, Ard Tiarna 1577
   I                     I---Dermot
   I                     I   ==> O'Crowley MacFyneen Sept, Tiarna,sup. 1615
   I                     I                    
   I                     I---  Donogh ---I   
   I                     I---  Teige  ---I==> O'Crowley Muskerry
   I                     I---  Conor  ---I
   I                              I  
   I                              I==> Comte Marianus O'Crowley France
   I=>O'Crowley na Madery Sept=è David na Madery, Tiarna, 1573
   I                                  I
   I                                  I-- Teige na Madery, Tiarna 1641
   I--Auliffe, Ard Tiarna 1484 – circa 1500
         I-Teige Mahilighigh buy, Ard Tiarna circa 1530=>O'Crowley Buy sept
         I          I
         I          I---David buy d.1617
         I                 I
         I                 I---- Teige buy, Ard Tiarna 1641,
         I                       transplanted to Clare 1659
         I---Cormac of Carbery, Ard Tiarna d.1562
         I                I----------------------Dermot Ard Tiarna 1590
               I---Teige MacDermot "Furiosus" alias Brannagh, 
               I   Ard Tiarna 1600-1618
               I---Fyneen MacDermot alias Brannagh, Ard Tiarna d.1622
                       I---David alias Brannagh, Ard Tiarna d.1638
                                 I---Teige alias Brannagh
                                     Ard Tiarna d.1640



Map of Kilshallow O'Crowley Lordship and O'Crowley other lordships


O'Crowley Clan Expansion.jpg





The O'Crowleys were included into the historical process of infeudisation under the auspices of the Tudor monarchs Henry VII and Henry VIII. The English Kings recognising the Gaelic Chiefs as Lords under their paramount Lords the MacCarthys. But the Gaelic Chiefs would still seek to retain and protect their native independence (their traditional powers derived from their clan by the Irish or Brehon Laws). The Nine-Year War and the battle of Kinsale in 1601 with the resulting English campaign will provide this opportunity. As would be expected by nature and profession the O'Crowley clan fought on the Gaelic side. The MacCarthy Reagh cooperated with the English, possibly enticing a certain policy of neutrality while Florence, self styled The MacCarthy Mor, and Dermot Moyle, his two cousins and brothers openly rebelled.

In 1594 a pardon was issued including Donogh Grana (ugly) McCormock O'Crowley and Deirmod ny Mroc (of the badgers) McCormock O'Crowley described as "Florence Carties men in County cork". In the same year while Florence was imprisoned in the tower in London, was to be examined among his "followers, cosins and kinsmen in Carbery Teige MacDonell I Crooly alias Brannagh" (The O'Crowley, Teige MacDermot). In same year again, Florence wrote "to som of mine owne men, namely Mulraney O’Crowley and Edward Seaback who I sent to keep the castle of Timoleague for me". In April 1600 Carew writes that among Florence friends most likely to revolt if the Spaniards would land in South Munster are the O'Crowleys. Subsequently on October 29th Carew took from Florence followers and Chief dependants separate pledges, these included the two O'Sullivans, the two O'Donoghues, McFynnen, O'Crowley and O'Mahony Carbery. As a result, Carew issued pardons to ease the country. In September 1601 the Spaniards land in Kinsale and the rebellion spreads out. In November Carew writes to the Lord Deputy "therefore, the Lord Deputy is to take heed of these and of the Mahownes and Crowlies".

With the Gaelic defeat at the battle of Kinsale and O'Neill and O'Donnell return to Ulster left the Carbery clans still in rebellion to face Carew's army. Resistance continued, in March 1602 Carew wrote to Donal O'Brien, Earl of Thomond and commander of the forces in Munster "Dermod Moyle MacCarthy is most assisted by the O'Crowleys; have a special care to prosecute him and his assistants".

In January 1603 the O'Crowleys were among a force lead by the MacCarthy of Phale and the bishop-elect of Ross Owen MacEgan which met the English army at the battle of Ballineen on the South border of Kilshallow. In Carew's Pacata Hibernia and in Don Philip O'Sullivan Beare's History of Ireland there is a reference of this battle; "The Irish foot were routed by the Royalist cavalry. The White Knight, commander of the English troops, pressed eagerly on the rear of the fugitives, and having followed Thady O'Crowley (The O'Crowley), surnamed “Furiosus”, into groung unsuitable for horse, he dismounted, and attacking with his sword, was deprived by Furiosus of two fingers, his signet ring, ear, and horse".

After the battle of Ballineen all resistance stoped in Carbery, however some of the O'Crowleys participated to the famous march of O'Sullivan Beare to the north. They were assigned the task of foraging and opening the epic march to Breifny. The O'Crowleys constituted the rear guard of O'Sullivan Bear and fought a pitch battle allowing the Gaelic troops to cross the Shannon safely into Clare. Some of these O'Crowleys will cross as well and settle in Clare.


After the 9 Year War land ownership changed through a combination of three factors. The English administration disposed of the lands of deceased O'Crowleys, some of the lands were granted to Lords who had not been involved in the rebellion; O'Hurley, The MacCarthy Reagh, Coppingers. These were subsequently granted to O'Crowleys or English protestants. Finally, under financial pressure The O'Crowley mortgaged and ultimately sold most of his demesne and had to move into the Parish of Kinneigh. In the Parish of Kilnagross, previously entirely owned by the O'Crowleys the Tiarna Lordship of O'Crowley MacFyneen of Dromgarrif was suppressed. The O'Crowleys maintained some of their lands in Fanlobbus but mostly in Kinneigh (na Maddery and The O'Crowley) and Skeaff (O'Crowley Og).

By the war of 1641 the Kilshallow Lordship had been reduced by 25 %, all in all between 1615 and 1641the O’Crowleys lost 40 % of their lands. The following war of 1641 during which 27 O'Crowleys were outlawed, all styled "Gentleman" except one (Yeoman) will bring total ruin with all the lands forfeited and the clan abolished by 1659.


The O'Crowley Clan today

After the confiscation of 1659 the clan structure is officially broken, the Chieftainship is no longer maintained since Brehon or Gaelic laws are fully abolished. However, in 1659 we find Teige O'Crowley Gentleman and his two sons Fyneen and David holding Cappacanon in County Clare, Parish of Tomgreary. This Teige maybe have been the last chief in 1642.

In France, Marianus O'Crowley from the O'Crowley MacFyneen branch attains the rank of Count and General of Light Cavalry of Louis XIV. His genealogy was duly recorded and claims to be from the senior chiefly line. In his papers he signs "Comte d'O'Cruoly" or if in English "Sir Miles O'Cruoly" - his coats of arms bear a Comital crown. The Book of Munster further gives the pedigree of an assumed Chief in 1702, through David, Auliffe, Teige Mahilighigh, Cormac, Auliffe and Dermot.

In 1971 the clan was officially reformed along with a clan council and elected honorary Taoiseach and Tanaiste. Since then the clan has a lively life holding clan gatherings every three years in West Cork, sustaining cultural activies but also promoting the bonds with the Crowleys from abroad.

The last Taoiseach were; Dr Seamus Crowley, from Cork Florence Crowley, from Bandon Charles Crowley, from Bandon Tom Crowley, from Ohio Liam Crowley, from Clancoolbeg, Bandon Marian Chamberlain Crowley, from North Carolina Jerry Crowley, from Cross Mahon, Bandon Michael-Patrick O'Crowley, from France and Ireland, a direct descendant of Fyneen O’Crowley Chief in 1577.

Book Available

Michael-Patrick Crowley's book on The Origins and History of the Crowley Clan is now available for purchase. This 200-plus page book is well written and has many illustrations. Cost is $25 US (or equivalent) per copy, plus shipping ($10 air, $6 surface). Michael will donate $5 per copy to the Crowley Castle Project. Order directly from:

Michael-Patrick Crowley
25 Avenu de L'Europe
92310 Sevres