Campbell's Farewell to Redcastle

The origins of this tune are unknown.

It may refer to Sir Donald Campbell who was given the Barony of Red Castle in Angus by Robert the Bruce, whom he supported in the Wars of Independence. Sir Donald's son married into money and moved to Ayrshire, taking on the new title Lord of Loudon. Red Castle and its lands were sold to the Stewarts. This may be the 'Farewell to Redcastle' of this tune's title?