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 eventually lifted Bruce's excommunication. In May 1328 King Edward III of England signed the Treaty of Edinburgh-Northampton, which recognised Scotland as an independent kingdom, and Bruce as its king. In 1325 Robert I exchanged lands at Cardross for those of Old Montrose in Angus with Sir David Graham. It was to be here that Robert would build the manor house that would serve as his favoured residence during the final years of his reign. The extant chamberlain's accounts for 1328 detail a manor house at Cardross with king's and queen's chambers and glazed windows, a chapel, kitchens, bake- and brew-houses,