English: Buchanan was a Latin scholar of European renown who taught on the Continent and was at one time imprisoned by the Inquisition. He spent two years of his incarceration translating the Psalms of David into Latin. It was Buchanan who first applied the term 'Celtic' to his native Gaelic culture, thus linking the pre-Roman inhabitants of Iron Age Britain to the Kelts of Europe. In 1561, he returned to Scotland and embraced the reformed religion. He tutored Mary, Queen of Scots, whom he denounced after the murder of her husband, Darnley. In 1567, he was appointed the first lay moderator of the General Assembly of the Church of Scotland. In 1570, he became tutor to the four-year-old James VI, entrusted with giving the young king a protestant education intended to turn him against his mother and ideas of rule by divine right. The precise location of his grave within the kirkyard is unknown.