Deda mac Sin (Deda, son of Sen) was a prehistoric king of the

Érainn The Iverni (, ') were a people of early Ireland first mentioned in Ptolemy's 2nd century ''Geography'' as living in the extreme south-west of the island. He also locates a "city" called Ivernis (, ') in their territory, and observes that this se ...

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

, possibly of the 1st century BC. Variant forms or spellings include Ded, Dedu, Dedad, Degad, Dega, Dego, Deguth and Daig, with some of these occurring as genitives although usage is entirely unsystematic, besides the rare occurrence of the obvious genitive Dedaid. He is the eponymous ancestor of the Clanna Dedad, and may also have been a

King of Munster The kings of Munster () ruled the Kingdom of Munster in Ireland from its establishment during the Irish Iron Age until the High Middle Ages. According to Gaelic traditional history, laid out in works such as the ''Book of Invasions'', the earli ...

. Through his sons

Íar mac Dedad Íar mac Dedad (Íar, son of Deda mac Sin) was a legendary King of Munster. He is the great grandfather, or in some sources more distant ancestor, of Eterscél Mór, and grandfather (or great-grandfather) of the famous Conaire Mór, both High Kings ...

and

Dáire mac Dedad Dáire mac Dedad (Dáire, son of Dega) is the eponymous ancestor of the Dáirine of Munster and father of the legendary Cú Roí mac Dáire. These further associate him with the prehistoric Darini of Ulster. He is probably identical with Dáire Do ...

, Dedu is an ancestor of many famous figures from legendary

, including his "grandsons" (giving or taking a generation) Cú Roí mac Dáire and Eterscél, "great-grandsons" (again)

Conaire Mór Conaire Mór (the great), son of Eterscél, was, according to mediaeval Irish legend and historical tradition, a High King of Ireland sometime during the 1st century BC or 1st century AD. His mother was Mess Búachalla, who was either the daugh ...

and Lugaid mac Con Roí, and more distant descendant

Conaire Cóem Conaire Cóem ("the beautiful"), son of Mug Láma, son of Coirpre Crou-Chend, son of Coirpre Firmaora, son of Conaire Mór, was, according to medieval Irish legend and historical tradition, the 111th High King of Ireland. He came to power on the ...

. A third son was Conganchnes mac Dedad. Through these, Dedu is also an ancestor of several historical peoples of both Ireland and

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

, including the

Dál Riata Dál Riata or Dál Riada (also Dalriada) () was a Gaels, Gaelic Monarchy, kingdom that encompassed the Inner Hebrides, western seaboard of Scotland and north-eastern Ireland, on each side of the North Channel (Great Britain and Ireland), North ...

, Dal Fiatach,

Múscraige The Múscraighe (older spelling: Músgraige) were an important Érainn people of Munster, descending from Cairpre Músc, son of Conaire Cóem, a High King of Ireland. Closely related were the Corcu Duibne, Corcu Baiscind, both of Munster, and a ...

Corcu Duibne The Corcu Duibne (Modern ), which means "seed or tribe of Duibhne" (the name of a goddess), was a notable kingdom in prehistoric and medieval County Kerry, Ireland which included the Dingle Peninsula, the Iveragh Peninsula and connecting land ...

, and

Corcu Baiscind The Corcu Baiscind were an early Érainn people or kingdom of what is now southern County Clare in Munster. They descended from Cairpre Baschaín, son of Conaire Cóem, a High King of Ireland. Closely related were the Múscraige and Corcu Duibne, ...

, all said to belong to the Érainn (Iverni), of whom the Clanna Dedad appear to have been a principal royal sept. The generations preceding Dedu mac Sin in the extant pedigrees appear artificial. Eventually they lead through

Ailill Érann The Iverni (, ') were a people of early Ireland first mentioned in Ptolemy's 2nd century ''Geography'' as living in the extreme south-west of the island. He also locates a "city" called Ivernis (, ') in their territory, and observes that this se ...

to a descent from

Óengus Tuirmech Temrach Óengus Tuirmech Temrach, son of Eochaid Ailtlethan, was, according to medieval Irish legend and historical tradition, a High King of Ireland. He came to power after killing his predecessor, and his father's killer, Fergus Fortamail. His sons inc ...

and thus a distant kinship with the

Connachta The Connachta are a group of medieval Irish dynasty, dynasties who claimed descent from the legendary High King of Ireland, High King Conn of the Hundred Battles, Conn Cétchathach (Conn of the Hundred Battles). The modern western Provinces of ...

and

Uí Néill The Uí Néill (; meaning "descendants of Niall") are Irish dynasties that claim descent from Niall Noígíallach (Niall of the Nine Hostages), a historical King of Tara who is believed to have died around c. 405. They are generally divided ...

, whose own pedigree is in fact unreliable before Túathal Techtmar. A proto-historical sept of the Clanna Dedad are known as the

Dáirine The Dáirine (Dárine, Dáirfine, Dáirfhine, Dárfine, Dárinne, Dairinne), later known dynastically as the Corcu Loígde and associated, were the proto-historical rulers of Munster before the rise of the Eóganachta in the 7th century AD. They ...

, descending from Dáire mac Dedad and/or

Dáire Doimthech Dáire Doimthech (Dáire "poor house"), alias Dáire Sírchréchtach ("the ever-wounded"), son of Sithbolg, was a legendary King of Tara and High King of Ireland, and one of the eponymous ancestors of the proto-historical Dáirine and historical ...

(Sírchrechtach), and are later known as the

Corcu Loígde The Corcu Loígde (Corcu Lóegde, Corco Luigde, Corca Laoighdhe, Laidhe), meaning Gens of the Calf Goddess, also called the Síl Lugdach meic Itha, were a kingdom centred in West County Cork who descended from the proto-historical rulers of M ...

. Alternatively this may be used synonymously, with some confusion created by their identification with the

Darini The Darini (Δαρῖνοι) (manuscript variant: Darnii �άρνιοι were a people of ancient Ireland mentioned in Ptolemy's 2nd century ''Geography'' as living in south Antrim and north Down. Their name implies descent from an ancestor called ...

of prehistoric

Ulster Ulster (; or ; or ''Ulster'') is one of the four traditional or historic provinces of Ireland, Irish provinces. It is made up of nine Counties of Ireland, counties: six of these constitute Northern Ireland (a part of the United Kingdom); t ...

. In any case, the Darini and Iverni are clearly related. According to the Book of Glendalough (Rawlinson B 502) and Laud 610 pedigrees, a brother of Dedu was Eochaid/Echdach mac Sin, from whom descend the

Dál Fiatach Dál Fiatach was a Gaelic Ireland, Gaelic dynastic-grouping and the name of their territory in the north-east of Ireland, which lasted throughout the Middle Ages until their demise in the 13th century at the hands of Normans in Ireland, Normans ...

of Ulster. But alternatively they descend directly from Cú Roí mac Dáire, and thus from the Clanna Dedad proper. The precise relation of the Dál Fiatach to the

Ulaid (Old Irish, ) or (Irish language, Modern Irish, ) was a Gaelic Ireland, Gaelic Provinces of Ireland, over-kingdom in north-eastern Ireland during the Middle Ages made up of a confederation of dynastic groups. Alternative names include , which ...

of the

Ulster Cycle The Ulster Cycle (), formerly known as the Red Branch Cycle, is a body of medieval Irish heroic legends and sagas of the Ulaid. It is set far in the past, in what is now eastern Ulster and northern Leinster, particularly counties Armagh, Do ...

, rivals of the Clanna Dedad, is lost to history.

Eoin MacNeill Eoin MacNeill (; born John McNeill; 15 May 1867 – 15 October 1945) was an Irish scholar, Irish language enthusiast, Gaelic revivalist, nationalist, and politician who served as Minister for Education from 1922 to 1925, Ceann Comhairle of D ...

finds the

Conaille Muirtheimne Conaille Muirthemne was a Cruithin kingdom located in County Louth, Ireland, from before 688 to after 1107 approximately. Overview The Ulaid according to historian Francis John Byrne 'possibly still ruled directly in Louth as far as the Boyne i ...

to also descend from Dedu mac Sin, from another son Conall Anglonnach, believing they are quite mistakenly thought to be

Cruthin The Cruthin (; or ; ) were a people of early medieval Ireland. Their heartland was in Ulster and included parts of the present-day counties of Antrim, Down and Londonderry. They are also said to have lived in parts of Leinster and Connacht ...

, as found in later genealogies. Dui Dallta Dedad was a foster-son of Dedu. There is also an

Ogham Ogham (also ogam and ogom, , Modern Irish: ; , later ) is an Early Medieval alphabet used primarily to write the early Irish language (in the "orthodox" inscriptions, 4th to 6th centuries AD), and later the Old Irish language ( scholastic ...

of Dedu (Ogam Dedad) found in the '' Book of Ogams''. Over one third of all Irish ogham inscriptions are found in the lands of his descendants the Corcu Duibne.

The Sil Conairi

The Síl Conairi were those septs of the Clanna Dedad descended from

, namely the

, and

Corcu Baiscinn The Corcu Baiscind were an early Érainn people or kingdom of what is now southern County Clare in Munster. They descended from Cairpre Baschaín, son of Conaire Cóem, a High King of Ireland. Closely related were the Múscraige and Corcu Dui ...

. The first, presumably settling in far northeastern Ulster in the prehistoric period, would famously go on to found the

Kingdom of Scotland The Kingdom of Scotland was a sovereign state in northwest Europe, traditionally said to have been founded in 843. Its territories expanded and shrank, but it came to occupy the northern third of the island of Great Britain, sharing a Anglo-Sc ...

. The Royal Family of Scotland, the

House of Dunkeld The House of Dunkeld (in or "of the Caledonians") is a historiographical and genealogical construct to illustrate the clear succession of Scottish kings from 1034 to 1040 and from 1058 to 1286. The line is also variously referred to by historian ...

, were described as the "seed of Conaire Mór" as late as the twelfth century. Through the House of Dunkeld and Conaire Mór, Dedu mac Sin is an ancestor of the modern

British royal family The British royal family comprises Charles III and other members of his family. There is no strict legal or formal definition of who is or is not a member, although the Royal Household has issued different lists outlining who is considere ...

. The last king in the direct male line from the Clanna Dedad and Sil Conairi was

Alexander III of Scotland Alexander III (; Modern Gaelic: ; 4 September 1241 – 19 March 1286) was King of Alba (Scotland) from 1249 until his death. He concluded the Treaty of Perth, by which Scotland acquired sovereignty over the Western Isles and the Isle of Man. ...

(d. 19 March 1286). The remaining Síl Conaire would settle and/or remain in Munster, where, although retaining their distinctive identity, they would be overshadowed first by their Dáirine (Corcu Loígde) kinsmen, and later fall under the sovereignty of the

Eóganachta The Eóganachta (Modern , ) were an Irish dynasty centred on Rock of Cashel, Cashel which dominated southern Ireland (namely the Kingdom of Munster) from the 6/7th to the 10th centuries, and following that, in a restricted form, the Kingdom of De ...

. But it appears the Síl Conaire, and especially the Múscraige, actually acted as prominent facilitators for the latter, and this would presumably have been in opposition to the Dáirine. A late and unexpected king of Munster from the Múscraige was Flaithbertach mac Inmainén (d. 944). The birth, life, and fall of Conaire Mór are recounted in the epic tale ''

Togail Bruidne Dá Derga ''Togail Bruidne Dá Derga'' (''The Destruction of Da Derga's Hostel'') is an Irish tale belonging to the Ulster Cycle of Irish mythology. It survives in three Old Irish, Old and Middle Irish recensions, it is part of the Lebor na hUidre, Book ...

''. Two distantly related tales of more interest to genealogists are '' De Síl Chonairi Móir'' and ''De Maccaib Conaire''. In these he is confused with his descendant

The Dál Fiatach and Cú Roí

The descent of the

princes of Ulster from Dedu mac Sin is less secure, but nonetheless is supported by independent medieval sources (and contradicted by others).

The Dáirine (Corcu Loígde)

As early as 1849, the great Irish scholar John O'Donovan noted that the pedigree of the Corcu Loígde, the leading historical descendants of the Dáirine, is corrupt for many of the generations preceding the legendary monarch Lugaid Mac Con.

Descent of the Clanna Dedad

Skipped generations are given in the notes. *

Sen mac Rosin Sen may refer to: Surname *Sen is a surname used by Magars and Thakuri in Nepal * Sen (surname), a Bengali surname * Şen, a Turkish surname * A variant of the Serer patronym Sène Currency subunit * Etymologically related to the English wo ...

Dedu mac Sin Deda mac Sin (Deda, son of Sen) was a prehistoric king of the Érainn of Ireland, possibly of the 1st century BC. Variant forms or spellings include Ded, Dedu, Dedad, Degad, Dega, Dego, Deguth and Daig, with some of these occurring as genitives ...

a quo Clanna Dedad ***

****

Ailill Anglonnach Ailill (Ailell, Oilioll) is a male name in Old Irish. It is a prominent name in Irish mythology, as for Ailill mac Máta, King of Connacht and husband of Queen Medb, on whom Shakespeare based the Fairy Queen Mab. Ailill was a popular given name i ...

***** Éogan ****** Eterscél *******

a quo Síl Conaire ******** Mug Láma *********

********** Eochaid (Cairpre) Riata (Rigfhota), a quo ***********

************ Erc of Dalriada ************* Fergus Mór ************** Domangart Réti *************** Gabrán mac Domangairt, a quo **************** Cenél nGabráin *****************

House of Alpin The House of Alpin, also known as the Alpinid dynasty, Clann Chináeda, and Clann Chinaeda meic Ailpín, was the kin-group which ruled in Pictland, possibly Dál Riata, and then the kingdom of Alba from Constantine II (Causantín mac Áeda) ...

*****************

*************** Comgall mac Domangairt, a quo **************** Cenél Comgaill *************

Loarn mac Eirc Loarn mac Eirc was a possible king of Dál Riata who may have lived in the 5th century. He was buried on Iona.J. M. P. Calise, Pictish sourcebook, Greenwood Press, 2002. Loarn's main significance is as the eponymous An eponym is a noun after ...

, a quo ************** Cenél Loairn *************** House of Moray **************** Mormaers of Moray ************* Óengus Mór mac Eirc, a quo **************

Cenél nÓengusa The Cenél nÓengusa were a kin group who ruled the island of Islay, and perhaps nearby Colonsay, off the western coast of Scotland in the early Middle Ages. The Senchus fer n-Alban, a census and genealogy of the kingdom of Dál Riata, lists t ...

********** Cairpre Músc, a quo ***********

*********** Corc Duibne, a quo ************

********** Cairpre Baschaín, a quo ***********

***

/ Dairi Sirchrechtaig /

**** Cú Roí mac Dáire ***** Lugaid mac Con Roí ***** Fuirme mac Con Roí ****** (F)Iatach Find, a quo *******

****

*****

*** Conganchnes mac Dedad *** Conall Anglonnach mac Dedad, a quo ****

** Eochaid (Echdach/Echach) mac Sin *** Deitsin/Deitsini **** Dlúthaich/Dluthaig ***** Dáire/Dairi ****** Fir furmi Laud 610 variant ******* Fiatach Finn / Fiachach Fir Umai Rawlinson B 502 variant ********

Notes

References

* John Bannerman, ''Studies in the History of Dalriada''. Edinburgh: Scottish Academic Press. 1974 *

Francis John Byrne Francis John Byrne (1934 – 30 December 2017) was an Irish historian. Born in Shanghai where his father, a Dundalk man, captained a ship on the Yellow River, Byrne was evacuated with his mother to Australia on the outbreak of World War II. A ...

, ''Irish Kings and High-Kings''.

Four Courts Press Four Courts Press is an independent Irish academic publishing house, with its office at Malpas Street, Dublin 8, Ireland. Founded in 1970 by Michael Adams, who died in February 2009, its early publications were primarily theological, notably ...

. 2nd revised edition, 2001. * Hector Munro Chadwick, ''Early Scotland: the Picts, the Scots and the Welsh of southern Scotland''.

Cambridge University Press Cambridge University Press was the university press of the University of Cambridge. Granted a letters patent by King Henry VIII in 1534, it was the oldest university press in the world. Cambridge University Press merged with Cambridge Assessme ...

. 1949. * Margaret E. Dobbs
The History of the Descendants of Ir
in '' Zeitschrift für celtische Philologie 13'' (1921): 308–59; continued in ''Zeitschrift für celtische Philologie 14'' (1923): 44–144. * Margaret E. Dobbs
Side-lights on the Táin age and other studies
Dundalk: WM. Tempest. 1917. * John V. Kelleher
"The Pre-Norman Irish genealogies"
in ''Irish Historical Studies 16, No. 62'' (1968): 138–153. * John V. Kelleher
"The Táin and the Annals"
in Ériu 22 (1971): 107–27 *

"Early Irish Population Groups: their nomenclature, classification and chronology"
in ''Proceedings of the

Royal Irish Academy The Royal Irish Academy (RIA; ), based in Dublin, is an academic body that promotes study in the natural sciences, arts, literature, and social sciences. It is Ireland's premier List of Irish learned societies, learned society and one of its le ...

"Notes on Irish Ogham Inscriptions"
in ''Proceedings of the Royal Irish Academy''. 1909. pp. 329–70 *

Kuno Meyer Kuno Meyer (20 December 1858 – 11 October 1919) was a German scholar, distinguished in the field of Celtic philology and literature. His pro-German stance at the start of World War I in the United States was a source of controversy. His brothe ...

(ed.)
"The Laud Genealogies and Tribal Histories"
in '' Zeitschrift für celtische Philologie 8'' (1912): 291–338. * Michael A. O'Brien (ed.) with intr. by John V. Kelleher, ''Corpus genealogiarum Hiberniae''. DIAS. 1976. / partial digital edition:

Donnchadh Ó Corráin Donnchadh Ó Corráin (28 February 1942 – 25 October 2017) was an Republic of Ireland, Irish historian and professor emeritus of medieval history at University College Cork. He earned his BA in history and Irish from UCC, graduating in 1964. ...

(ed.)
Genealogies from Rawlinson B 502
University College, Cork
Corpus of Electronic Texts
1997. * John O'Donovan (ed. & tr.), "The Genealogy of Corca Laidhe", i
Miscellany of the Celtic Society
Dublin: Printed for The Celtic Society. 1849
alternative scan
* T. F. O'Rahilly, ''Early Irish History and Mythology''.

Dublin Institute for Advanced Studies The Dublin Institute for Advanced Studies (DIAS) () is a statutory independent research institute in Dublin, Ireland. It was established, under the Institute For Advanced Studies Act 1940, by the government of the then Taoiseach, Éamon de Vale ...

. 1946. *

Julius Pokorny Julius Pokorny (12 June 1887 – 8 April 1970) was an Austrian-Czech linguist and scholar of the Celtic languages and of Celtic studies, particularly of the Irish language, and a supporter of Irish nationalism. He held academic posts in Austrian ...

"Beiträge zur ältesten Geschichte Irlands (3. Érainn, Dári(n)ne und die Iverni und Darini des Ptolomäus)"
in '' Zeitschrift für celtische Philologie 12'' (1918): 323–57. ;

Dictionary of the Irish Language ''Dictionary of the Irish Language: Based Mainly on Old and Middle Irish Materials'' (also called "the ''DIL''"), published by the Royal Irish Academy, is the definitive dictionary of the origins of the Irish language, specifically the Old Irish, ...

eDIL – Dictionary of the Irish Language
Letter: D1 (D-Degóir), Columns 207 & 208 ;Ireland's History in Maps

by Dennis Walsh

by Dennis Walsh {{DEFAULTSORT:Deda Mac Sin Legendary Irish kings Scottish clans