The Buchan Barons of Auchmacoy were staunch royalists and supporters of the House of Stuart. Thomas Buchan who was the third son of chief James Buchan of Auchmacoy, was a professional soldier who fought in both France and Holland. He served in Douglas's Scots Regiment that was raised for the king of France. In 1686 he was commissioned as colonel in the Earl of Mar’s regiment by James VII of Scotland. He later joined John Graham, 1st Viscount Dundee. After Dundee was killed at the Battle of Killiecrankie in 1689 Buchan was appointed as commander-in-chief of all Jacobite forces in Scotland and received his commission from the king in Ireland. General Buchan harried the enemy with his force of twelve hundred foot soldiers. However, on 1 May 1690 he was surprised and defeated by a strong government force under General Hugh Mackay at the Battle of Cromdale. Buchan however escaped and joined forces with the Clan Farquharson who encouraged him to take the offensive again and they marched from Abergeldie to the Mearns. He was opposed by the Master of Forbes who had a strong force of cavalry, but Buchan dispersed his troops to give the appearance of numerical superiority and Forbes retreated to Aberdeen, causing panic in the city. General Hugh Mackay and his forces then marched to intercept Buchan and as a result the Highlanders under Buchan began to drift away.