[1] Gartnait and Drest may have been sons of Domnall Brecc, who was king of Dál Riata from c. 629 until he was killed in 642.
[1] His accession to the kingship may be connected to the Battle of Luith Feirn recorded in the Annals of Ulster as taking place in 664,[2] or Oswiu may have forced an interregnum on the kingdom from 663–666,[3] after the death of Drest's brother Gartnait in 663.
[5] Drest was expelled from his kingdom in 671, an event normally connected with the failed Pictish revolt against Northumbrian rule that culminated in crushing defeat at the hands of Ecgfrith of Northumbria at the Battle of Two Rivers.
[5] Stephen of Ripon records in his Vita Sancti Wilfrithi (Life of St Wilfrid) that the Picts had "gathered together innumerable nations (gentes) from every nook and corner in the north",[6] suggesting that Drest had joined forces with other territories which were otherwise not politically united.
[4] After his expulsion Drest continued to receive attention from Irish annals, suggesting he remained in the orbit of the Abbey of Iona, until his death in 677.