Guðrøðr evidently pursued a more aggressive policy than his father, and the following year appears to have lent military assistance to Muirchertach Mac Lochlainn, King of Cenél nEógain in the latter's bid for the high-kingship of Ireland.

Not long afterwards, Guðrøðr faced a dynastic challenge from his brother-in-law, Somairle mac Gilla Brigte, Lord of Argyll, whose son, as a grandson of Óláfr, possessed a claim to the throne.

Although Guðrøðr may have attempted to avert any succession disputes between his descendants, Rǫgnvaldr and his younger brother, Óláfr svarti, eventually fought each other over the throne, and the resulting conflict carried on into later generations.

[32] Several contemporary sources concerning Fergus' descendants suggest that he was married to an illegitimate daughter of Henry I, and that this woman was the mother of at least some of his offspring, including Affraic herself.

The marital alliance forged between Óláfr and Fergus gave the Crovan dynasty valuable familial-connections with the English Crown, one of the most powerful monarchies in western Europe.

[50] By the mid-part of the twelfth century, however, the ageing king's realm may well have begun to buckle under the strain,[51] as perhaps evidenced by the depredations wrought on the Scottish mainland by Óláfr's leading ecclesiast, Wimund, Bishop of the Isles.

[59][note 3] Once in control, the chronicle reveals that the men fortified themselves against forces loyal to Guðrøðr, the kingdom's legitimate heir, by launching a preemptive strike against his maternal grandfather, Fergus.

[63] Additionally, the account of incessant inter-dynastic strife amongst the ruling family of Galloway, as recorded by the twelfth-century Vita Ailredi, suggests that Fergus may have struggled to maintain control of his lordship by the mid 1150s, and may also explain his failure to come to Guðrøðr's aid following Óláfr's death.

The dynastic-challenges faced by Malcolm, and the ebb of Scottish influence in the Isles, may partly account for Guðrøðr's success in consolidating control of the kingdom, and may be perceptible in the seemingly more aggressive policy he pursued as king in comparison to his father.

[92][note 6] Although the precise partitioning is unrecorded and uncertain, the allotment of lands seemingly held by Somairle's descendants in the twelfth and thirteenth centuries could be evidence that he and his son gained the southernmost islands of the Hebrides, whilst Guðrøðr retained the northernmost.

[96] According to the thirteenth-century Orkneyinga saga, the contemporary Orcadian warlord Sveinn Ásleifarson had connections in the Isles, and overcame Somairle in battle at some point in the twelfth century.

[115] Somairle's deal with Scottish Crown may also have been undertaken not only in an effort to ensure that his own authority in the Isles was recognised by Malcolm, but to limit any chance of Guðrøðr receiving future royal support from the Scots.

[118] In late 1160 or early 1161, Guðrøðr distinguished himself in the ongoing civil war in the Norwegian realm, as evidenced by Hákonar saga herðibreiðs within the thirteenth-century saga-compilation Heimskringla.

[133] Although it is possible that Dubgall was able to secure power following his father's demise,[134] it is evident from the Chronicle of Mann that the kingship was seized by Guðrøðr's brother, Rǫgnvaldr, before the end of the year.

[139][note 8] In an entry dated 1172, the chronicle states that Mann was invaded by a certain Ragnall mac Echmarcacha, a man who slaughtered a force of Manx coast-watchers before being slain himself in a later engagement on the island.

[152][note 10] Another possibility is that Ragnall's attack was somehow related to events in northern Ireland, where the Meic Lochlainn lost hold of the Cenél nEógan kingship to Áed Méith Ua Néill.

[165] In the winter of 1176/1177, the chronicle reveals that Guðrøðr was formally married to Muirchertach's granddaughter, Findguala Nic Lochlainn, in a ceremony conducted under the auspices of the visiting papal legate, Vivian, Cardinal priest of St Stephen in Celio Monte.

[188] In 1170 even more English troops flocked to Diarmait's cause, including Richard de Clare, Earl of Pembroke, who successfully stormed the Norse-Gaelic enclave of Waterford.

[198] The account of events recorded by Expugnatio Hibernica and the twelfth- to thirteenth-century La Geste des Engleis en Yrlande indicate that Ascall's forces consisted of heavily armoured Islesmen and Norwegians.

[203][note 15] Whilst it is possible that Guðrøðr may have been enticed to assist the Irish through the promise of financial compensation, and perhaps the possession of any vessel his fleet captured in the operation, there is reason to suspect that the Islesmen were disquieted by prospect of permanent English authority in the region.

[203] Although the operation was one of the greatest military mobilisations that the Irish mustered in the twelfth century,[205] the blockade was ultimately a failure, and Dublin remained firmly in the hands of the English.

[209] The participation of monarchs such as Guðrøðr and William I, King of Scotland in the ceremony partly illustrates the imperial aspect of the Plantagenet authority in the British Isles.

He reached Down (modern day Downpatrick), drove off Ruaidrí Mac Duinn Sléibe, King of Ulaid, consolidated his conquest, and ruled with a certain amount of independence for about a quarter of a century.

[227] Another contributing factor to the alliance between Guðrøðr and John may have been the Meic Lochlainn's loss of the Cenél nEógain kingship to the rival Uí Néill dynast Áed Méith in 1177.

[234] For example, Guðrøðr confirmed his father's charter to the abbey of St Mary of Furness, in which the monks of this Cistercian house were granted the right to select the Bishop of the Isles.

[236][note 17] In the reigns of Guðrøðr's succeeding sons, the Benedictine priory of St Bees continued to receive royal grants of Manx lands.

[254] Certainly, Guðrøðr's stay in Norway coincided with the Scandinavian visit of the papal legate Nicholas Breakspeare, Cardinal-Bishop of Albano,[255] a man who had been tasked to create Norwegian and Swedish ecclesiastical provinces in order to further extend the papacy's authority into the northern European periphery.

[274] Either Gamaliel or Reginald could have been the unnamed Bishop of the Isles who is stated by Robert's Chronica to have met with William and Henry II at Mont St Michel.

[289] There is also reason to suspect that Guðrøðr had another daughter,[290] as the Chronicle of Mann describes a thirteenth century Bishop of the Isles, a man named Reginald, to have been of royal birth,[291] and to have been a sister-son of Óláfr svarti.

[305] Although Rǫgnvaldr appears to have later forged an alliance with the Meic Somairle, and may have temporarily reunited the entire Kingdom of the Isles under his own leadership,[306] he was later opposed by Óláfr svarti, and the ensuing violent conflict between Guðrøðr's descendants carried on to further generations.