Following Robert I's successful consolidation of the Scottish kingship, Aonghus Óg and other members of his kindred were rewarded with extensive grants of territories formerly held by their regional opponents.

Certainly, Eóin Mac Domhnaill—Aonghus Óg's lawful son by Áine Ní Chatháin—held the chiefship by the 1330s, and became the first member of Clann Domhnaill to rule as Lord of the Isles.

[23] According to Hebridean tradition preserved by the seventeenth-century Sleat History, she was a daughter of Cailéan Mór Caimbéal, a leading member of the Caimbéalaigh.

Although this Norwegian girl was accepted by the magnates of the realm, and betrothed to the heir of Edward I, King of England, she perished on her journey to Scotland, and her death triggered a succession crisis.

[37] In 1296, after John ratified a military treaty with France, and refused to hand over Scottish castles to Edward I's control, the English marched north and crushed the Scots at Dunbar.

[45] During the short Balliol regime, Alasdair Mac Dubhghaill had been appointed Sheriff of Lorn, a position which made him the Scottish Crown's representative throughout much of the western seaboard, including Clann Domhnaill and Caimbéalaigh territories.

[46] If tradition preserved by the seventeenth-century Ane Accompt of the Genealogie of the Campbells is to be believed, Clann Dubhghaill overcame and slew Cailéan Mór in the 1290s.

[59] According to the highly reliable fourteenth-century poem The Brus, Aonghus Óg played an instrumental part in Robert's survival and was ever loyal to the Bruce.

Specifically, this source relates that, after Robert was defeated at Methven and Dalrigh in the summer of 1306, the king fled into the mountains and made for the coast of Kintyre, where he was protected by Aonghus Óg himself at Dunaverty Castle.

[60] Although the Bruce maintains that Aonghus Óg harboured the king at Dunaverty Castle,[61] contemporary evidence reveals that Robert I's men were already in possession of the fortress by March, having acquired it from a certain Malcolm le fitz l'Engleys.

[62] In fact, in the immediate aftermath of John Comyn's death, Robert secured control of several western fortresses (including that of Dunaverty), seemingly in an effort to keep a lane open for military assistance from Ireland or the Hebrides.

[69] There is reason to suspect that this account instead masks an historical incident in which the king fled from Kintyre to a Clann Domhnaill castle on Islay—perhaps Dunyvaig Castle—the next northernmost island.

[95] For instance, Aonghus Óg was granted the former Comyn lordship of Lochaber and the adjacent regions of Ardnamurchan, Morvern, Duror, and Glencoe;[96] whilst a certain Alasdair of the Isles received the former Clann Dubhghaill islands of Mull and Tiree.

[99] Later in the fourteenth century, Aonghus Óg's son, Eóin Mac Domhnaill, was granted the territories of Ardnamurchan, Colonsay, Gigha, Glencoe, Jura, Kintyre, Knapdale, Lewis, Lochaber, Morvern, Mull, and Skye.

[100] If this was indeed the case, the fact that Robert I later granted a significant portion of these territories (Lochaber, Kintyre, Skye, and lands in Argyll) to other magnates suggests that his conceivable concessions to Clann Domhnaill may have been undertaken with some reluctance.

Although the Bruce specifies that the Clann Domhnaill dynast to whom the king owed his salvation was Aonghus Óg, there is reason to question this claim.

[66] Furthermore, the claim that Aonghus Óg was Lord of Kintyre during this period could stem from the fact that, by the time the Bruce was composed, Eóin Mac Domhnaill was married to a daughter of the Robert II, and had gained this contested lordship by way of her tocher.

According to this source, the king's battalion was composed of men from Carrick, Argyll, Kintyre, the Hebrides (all of Angus Og Macdonald's Islesmen), and the Scottish Lowlands.

[140][note 17] Although every other pitched-battle between the Scots and the Anglo-Irish resulted in a Scottish victory,[146] the utter catastrophe at the Battle of Faughart cost Edward his life and brought an end to the Bruce regime in Ireland.

[159] Aonghus Óg died at some point after the Battle of Bannockburn—notwithstanding the Hebridean tradition preserved by the eighteenth-century Book of Clanranald and the Sleat History that dates his death to about 1300.

[162] Henry Lee, in his "History of the Clan Donald" states that Angus Og died at his castle in Finlaggan on Islay in 1330 and was buried at Iona.

[166] The political situation in the Hebrides is murky between this man's accession and the disaster at Faughart,[167] and it is possible that an after-effect of this defeat was a period of Clann Ruaidhrí dominance in the region.

[176] In fact, before the end of Robert I's reign, this son of Aonghus Óg appears to have administered Islay on behalf of the Scottish Crown,[177] and eventually came to be the first[178] Clann Domhnaill dynast to bear the title dominus insularum ("Lord of the Isles").

[185] According to the Sleat History, Áine Ní Chatháin's tocher consisted of one hundred and forty men from each surname that dwelt in the territory of her father, Cú Maighe na nGall Ó Catháin.

[189] In any case, this tocher appears similar to an historical one dating almost a century earlier, when a Clann Ruaidhrí bride brought over one hundred and sixty warriors to her Irish husband.

[190] The tradition of the Clann Domhnaill–Uí Catháin union is corroborated by the record of an English safe-conduct instrument granted to Áine Ní Chatháin, identified as the mother of Eóin Mac Domhnaill in 1338.

[191] At a later date, Áine Ní Chatháin appears to have remarried a member of Clann Aodha Buidhe,[192] a branch of the Ó Néill kindred.

[199] Another child of the couple may be the Áine Nic Domhnaill noted in the Clann Lachlainn pedigree preserved by the fifteenth-century manuscript National Library of Scotland Advocates' 72.1.1 (MS 1467).

[206] According to the Sleat History, an illegitimate daughter of Aonghus Mór was the mother of an early chiefly ancestor of Clann Mhic an Tóisigh.

"[208] Aonghus Óg appears as a character in the 2018 historical drama film Outlaw King, where he is portrayed by Scottish actor Tony Curran.