Clan Sweeney supporters of the powerful MacDougall Lords of Lorne who supported John Balliol as patriots, as long as John was king of Scotland. After the murder of John Comyn, the nephew of Balliol, by Bruce in 1306, the First War of Scottish Independence became at one and the same time a civil war. The Balliol and Comyn parties taking the side of the English in opposition to Bruce, crowned Robert I of Scotland on 25 March 1306. This was an era of constantly shifting alliances, and in 1301 John MacSween was in alliance with Aonghus Óg Mac Domhnaill, Lord of Islay
Niall mac Cailein Dovenald Chambel and Sir Nel Chambel by their lands and bodies". In the same year, Edward granted some Campbell lands to an English knight, Sir John Dovedale. Such judgments were both a cause and effect of deteriorating relations with the English crown. So when Robert decided to rebel in 1306, it is not surprising that Niall and Domhnall were among the would-be king's first adherents. Niall was present at Scone in March 1306 when Robert was crowned King of Scots. After the defeats Robert suffered at the Battle of Methven and Battle of Dalrigh, Niall was one of the men