The Battle of the Western Isles was a series of conflicts in 1585 and 1586 on the islands of Jura, Islay, Mull and Tiree, Scotland as well as the peninsula of Kintyre on the mainland. However, although the historic sources describe this as having taken place in the "Western Isles" which are now known as the Outer Hebrides, all of the aforementioned locations are actually in the Inner Hebrides. It was fought between the Clan Macdonald of Sleat and Clan MacDonald of Dunnyveg against the Clan Maclean. In 1585, the Macleans slaughtered a party of the MacDonalds of Sleat when they were mistakenly accused of stealing cattle and the MacDonalds of Sleat and Dunnyveg retaliated. James VI of Scotland intervened but the conflicts continued into 1586. After further intervention an Act of Parliament was passed which would levy fines on any clan chiefs who did not maintain peace and good order among their vassals.
The conflict on Jura
In the summer of 1585, Donald Gorm Mor of Sleat, chief of the Clan Macdonald of Sleat, along with a large following of men, left the Isle of Skye to pay a visit to Angus MacDonald of Islay, chief of the Clan MacDonald of Dunnyveg. However, because of a severe storm he was forced to seek shelter on the north of the Isle of Jura, which part belonged to Lachlan Mor Maclean, chief of Clan Maclean, who was seated at Duart Castle on the Isle of Mull. Another party, which included Hugh, son of Archibald the Clerk and a Macdonald descendant of Donald Herrach, were also driven by the same storm to Jura. These two men collected a large amount of cattle belonging to the Macleans who lived near to the place that Donald Gorm Mor had landed, and carried them off in their galleys. Their objective was to get Donald Gorm Mor into trouble. They knew that the Macleans would believe that the theft was committed by Donald Gorm Mor and hoped that the Macleans would attack him and put him to death. The men whose cattle had been stolen went straight to Lachlan Mor Maclean to make their complaint. Lachlan Mor Maclean sailed to Jura with a number of men and made a sudden attack on Donald Gorm Mor, who had no idea what had taken place. In the battle he killed sixty of the MacDonalds, but the rest of them, including Donald Gorm Mor, made their escape. The punishment that Lachlan Mor Maclean inflicted was monstrous.
Donald Gorm Mor then made his way to Skye, fully resolved to take vengeance on the Macleans. He dispatched messengers to the chieftains of the various branches of the Clan Donald, calling upon them to assist him in the attack. Lachlan Mor Maclean having killed a number of innocent men created feelings of indignation and vengeance among all the MacDonalds who committed acts of depredation on his lands in various quarters and threatened to invade the Isle of Mull. They did find out that the cattle had actually been stolen by two MacDonalds but still felt so indignant over the slaughter of their clansmen that they were unwilling to come to terms with Lachlan Mor Maclean.
The King's intervention
In September, 1585, James VI of Scotland wrote to the Chief of the Clan MacLeod, seated at Dunvegan Castle, requesting him to assist the Macleans against the MacDonalds and he also urged the MacDonalds at the same time to cease their hostilities. The MacDonalds therefore resolved to settle their disputes in a peaceful manner.
In the spring of 1586, Angus MacDonald of Islay went to Skye to consult with Donald Gorm Mor about a settlement with Lachlan Mor Maclean. On his return he called at Duart Castle to try to come to an amicable settlement with Lachlan Mor Maclean. The following day, Maclean seized both Angus and his attendants and threw them into prison until Angus agreed to renounce his claim to the Rinns of Islay. Angus also had to give his son James, and his brother, Ranald, as hostages to Lachlan until he received the lands as promised. The harsh treatment that Angus received from Maclean meant that he went back to Islay as a bitter enemy.