The MacDonalds and Campbells had a feud going back to 1500 - an neither side was lily-white (that is a term which only steeds can claim). Here's some more information.

The massacre had roots in the Campbell-MacDonald feud, which dated back to 1500. The Campbells were prosperous and ambitious - with friends in high places. The MacDonalds were notorious, particularly for their ability to make cattle "disappear".

In 1501 the Glen Coe MacDonalds (with others) captured the Campbell fortress on Loch Awe, rescuing Donald Dhu - the last Lord of the Isles. Donald Dhu had been imprisoned for more than 40 years by his Campbell grandfather.

For years skirmishes and raids took place around Glen Lyon. In the early years of the conflict 36 Glen Coe MacDonalds were hanged by Mad Colin Campbell of Glen Lyon. In 1646 the MacDonalds attacked the Campbells after a wedding, killing 36. In 1685, when the Campbells' power was at low ebb (two Earls of Argyll had been executed), the MacDonalds pillaged Campbell land and effectively ruined many families. Scottish leaders often took advantage of the longstanding feud as well. The Campbells fought with Cromwell and the MacDonalds fought with Montrose during the Civil War.