John Mackenzie (c.1480-c.1561), or "John of Killin", traditionally reckoned 9th of Kintail, was a Highland chief, being head of the Clan Mackenzie.
John was the son of Kenneth Mackenzie, 7th of Kintail (d.1492) by his second wife, or reputed wife, Agnes Fraser. The Mackenzies' origins lay in the Northwest Highlands, but the centre of their power had by the end of the 15th century shifted to Easter Ross. John succeeded his half-brother, Kenneth (died 1498-99) in the chiefship while still a minor. It is likely that he achieved his majority in 1501, which suggests that he was born in about 1480.
John is said to have been sent to be educated at Court in Edinburgh (pursuant to an Act of 1496, a legal requirement for boys in his station of life). However, the terms of a bond subscribed by him in favour of the Earl of Huntly suggest that he remained illiterate.
Mackenzie's uncle, Hector Roy Mackenzie of Gairloch, had been appointed tutor to Mackenzie's brother, Kenneth Mackenzie, 8th of Kintail, and on Kenneth's death was left in possession of the greater part of the clan lands. He challenged John's succession on the grounds of his illegitimacy, but was eventually compelled to come to terms with him. The traditional account records that John's men surrounded and set fire to Hector's house at Fairburn. More prosaically, Gregory’s History of the Western Highlands and Isles of Scotland states that:
Some traces of this dispute are to be found in public records of the time. An Act of the Lords of Council on 7 April 1511 described a summons issued by John against Hector Roy:
The Act continues:
Although John and Hector Roy appear ultimately to have made their peace, hostilities flared up again in the next generation. Hector Roy's son, John Glassich Mackenzie, is said to have renewed his father's claim to some or all of the clan's lands and died in mysterious circumstances in Eilean Donan. In 1551, John Mackenzie (9th of Kintail) and his son received a remission for his imprisonment.