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 queen dowager) are unlikely but not impossible. Bruce and his followers returned to the Scottish mainland in February in two groups. One, led by Bruce and his brother Edward, landed at Turnberry Castle and began a guerrilla war in south-west Scotland. The other, led by his brothers Thomas and Alexander, landed slightly further south in Loch Ryan, but they were soon captured and executed. In April, Bruce won a small victory over the English at the Battle of Glen Trool, before defeating Aymer de Valence, 2nd Earl of Pembroke, at the Battle of Loudoun Hill. At the same time, James