In origin the battle of Harlaw was a feudal dispute, but it must be viewed
in the context of growing late medieval conflict between Highland and
Lowland. The situation was also complicated by the fact that King James I
was imprisoned in England and thus royal authority was weak. Donald, Lord
of the Isles, having fought for control of Ross, now planned to strike
south east into Moray, towards Aberdeen. But there was substantial warning
of the impending campaign and so defensive preparations were put in hand
by the Earl of Mar in the spring and early summer of 1411.
As soon as he
was aware of the approach of the Highland forces, Mar marshalled his
troops at Inverurie. The Highland forces camped on the night of the 23rd
July on high ground near Harlaw. On the morning of the 24th the Earl of
Mar marched out of Inverurie to engage the Highland army.
It appears to have been an intense and close run fight but the sources
provide little detail and there is even conflict over the outcome, with
both sides claiming victory. What is clear is that Aberdeen was
successfully defended and the Highland forces departed without causing
significant destruction in the region.
I have no evidence that any Douglas was involved in the batle, though
it is a possibility. However, they did benefit from the power vacuum in
Scotland that followed the battle.