Drostan was a 7th-century Irish-Scottish abbot and saint who served as a disciple of St. Columba. A member of the Scoti royal family, he traveled from Ireland to Scotland as part of the Brethren of St. Columba around 563. He is most recognized for establishing the monastery at Old Deer in Aberdeenshire, where he served as abbot. Later in his life, he sought a more secluded existence as a hermit in Glenesk, where he continued to attract followers through his religious devotion.