Clan Donnachaidh the Battle of Methven in 1306. The clan asserts that Stout Duncan's relatives and followers (not yet known as Robertsons) supported Robert the Bruce at the Battle of Bannockburn in 1314. His descendants became known (in English or Scots) as the Duncansons, or Gaelic "Clann Dhònnchaidh", "Children of Duncan". Duncan is believed to have been killed at the Battle of Neville's Cross and was succeeded by Robert, from who the Clan Robertson takes its name. Robert's brother, Patrick, was the ancestor of the Robertsons of Lude who were the principal cadet branch. In 1394 a clan battle took place between
Robert the Bruce appear not to have expected the Scots to give battle here, and as a result had kept their forces in marching, rather than battle, order, with the archers − who would usually have been used to break up enemy spear formations − at the back, rather than the front, of the army. The English cavalry found it hard to operate in the cramped terrain and were crushed by Robert's spearmen. The English army was overwhelmed and its leaders were unable to regain control. Edward II was dragged from the battlefield, hotly pursued by the Scottish forces, and only just escaped