Ragnall mac Somairle (also known in Gaelic as Raghnall, Raonall, Raonull; in English as Ranald; in Latin as Reginaldus; and in Old Norse as Rögnvaldr, Røgnvaldr, Rǫgnvaldr; died 1191/1192 – c. 1210/1227)[note 1] was a significant late-twelfth-century magnate, seated on the western seaboard of Scotland.

Ragnall's now non-existent seal, which pictured a knight on horseback, also indicates that he attempted to present himself as an up-to-date ruler, not unlike his Anglo-French contemporaries of the bordering Kingdom of Scots.

Ragnall was a son of Somairle mac Gilla Brigte, Lord of Argyll (died 1164) and his wife, Ragnhildr, daughter of Óláfr Guðrøðarson, King of the Isles.

[28] In 1164, Somairle again rose against the King of Scots, and is recorded in various early sources to have commanded a massive invasion force of men from throughout the Isles, Argyll, Kintyre and Scandinavian Dublin.

[43] The patrons of this priory were members of Alan's own family,[44] a powerful kindred that had recently begun to expand its influence westwards from Renfrew, to the frontier of the Scottish realm and the fringes of Argyll.

[45][note 5] Since Bute seems to have fallen into the hands of this kindred at about the time of Ragnall's grant, it is possible that Alan took advantage of the internal conflict between the meic Somairle, and seized the island before 1200.

[66] The use of such seals by leading Norse-Gaelic lords, seated on the periphery of the kingdoms of Scotland and England, probably illustrates their desire to present themselves as up-to-date and modern to their contemporaries in Anglo-French society.

[70] The fact that two closely related Hebridean rulers, Ragnall and Rǫgnvaldr, shared the same personal names, the same grandfather, and (at times) the same title, has perplexed modern historians and possibly mediaeval chroniclers as well.

[74] Howden's account of events reveals that Haraldr and his family gained control of Moray early in 1196,[75] and charter evidence suggests that William and royal forces were in the north that summer.

[76] Although the Chronicle of Melrose appears to indicate that Hvarflǫð and Haraldr's eldest son was defeated in 1197,[77] it is possible that this event dates to 1196 instead and relates to William's aforesaid northern campaign.

Having received the king's message, the saga records that Rǫgnvaldr duly gathered an armed host from the Isles, Kintyre, and Ireland, and went forth into Caithness and subdued the region.

[84] Howden's account appears to confirm Rǫgnvaldr's participation in the region, albeit under slightly different circumstances, as it states that Haraldr approached the king and attempted to purchase the earldom.

[95][note 10] A recent reanalysis of the main extant version of Howden's chronicle has shown, however, that this particular part of the text originally read in Latin Reginaldus filius rex de Man, and was later altered to include Somairle's name above the last three words.

There are earlier instances of such claimants requesting Scottish kings for what they considered their birthright,[100] and William certainly did this when he granted Caithness to Haraldr Eiríksson, a grandson of Rǫgnvaldr Kali Kolsson, Earl of Orkney.

[111] According to Hebridean tradition preserved by the seventeenth-century Sleat History, at one point during Ragnall's tenure his followers fought and slew a certain "Muchdanach", ruler of Moidart and Ardnamurchan, and thereby acquired the latter's lands.

[112] Muchdanach may be identical to a certain "Murcardus", a man described by the Chronicle of Mann as one whose "power and energy" were felt throughout the Kingdom of the Isles, and whose slaying is recorded in 1188, the year of Rǫgnvaldr's assumption of the kingship.

[116] In the mid twelfth century, during the reign of Ragnall's maternal uncle Guðrøðr Óláfsson, King of the Isles (died 1187), the diocese came to be incorporated into the newly established Norwegian Archdiocese of Nidaros.

[119] In the early 1190s, the Chronicle of Mann reveals that Cristinus, Bishop of the Isles, an Argyllman who was probably a meic Somairle candidate, was deposed and replaced by Michael (died 1203), a Manxman who appears to have been backed by Rǫgnvaldr.

[122] In fact, the diocese first appears on record in Liber Censuum, a Papal document dating to the last decade of the twelfth century;[123] and it is possible that Cristinus, or an unknown successor,[124] or perhaps even Haraldr himself, was the first diocesan bishop.

[119] Although the early diocesan succession of Argyll is uncertain,[126] the jurisdiction itself appears to have lain outwith the domain of Rǫgnvaldr's direct control, allowing the meic Somairle to readily act as religious patrons without his interference.

[132][note 12] Whatever the case, the foundation of the Diocese of Argyll appears to have been a drawn-out and gradual process that was unlikely to have been the work of one particular man[136]—such as Somerled,[137] Dubgall, or Ragnall himself.

[138] Although the early diocese suffered from prolonged vacancies, as only two bishops are recorded to have occupied the see before the turn of the mid thirteenth century,[127] over time it became firmly established in the region, allowing the meic Somairle to retain local control of ecclesiastical power and prestige.

[142][note 14] In 1164, at a time when Somairle ruled the entire Kingdom of the Isles, the Annals of Ulster indicates that he attempted to reinstate the monastic familia on Iona under Flaithbertach's leadership.

The monastery's foundation charter dates to December 1203,[146] which suggests that Ragnall may have been responsible for its erection, as claimed by early modern tradition preserved in the eighteenth-century Book of Clanranald.

[148] Since the charter reveals that the monastery received substantial endowments from throughout the meic Somairle domain, the foundation appears to have been supported by other leading members the kindred,[149] such as Dubgall himself (if he was still alive) or his son, Donnchad.

[163] Although this source's claim that the nunnery was originally a Benedictine foundation is erroneous,[164] its statement that Bethóc was a "religious woman" is corroborated by the seventeenth-century record of an inscribed stone on the island, said to have read in Gaelic "Behag nijn Sorle vic Ilvrid priorissa".

[57] According to late Hebridean tradition, preserved in the garbled Sleat History, Ragnall was married to "MacRandel's daughter, or, as some say, to a sister of Thomas Randel, Earl of Murray".

[217] These unions appear to have been orchestrated to patch up relations between the meic Somairle and the Crovan dynasty, rival kindreds who had bitterly contested the kingship of the Isles for about sixty years.

[31] Unsupported claims made by the Book of Clanranald present Ragnall as "the most distinguished of the Gall or Gaedhil for prosperity, sway of generosity, and feats of arms", and report that he "received a cross from Jerusalem".

[222] The mid-sixteenth-century description of the Hebrides and the Islands of the Clyde authored by Donald Monro (died in or after 1575) reveals that Ragnall's reign was still remembered in the Isles during the sixteenth century.