Complex sentence: In 1457, Sir David Guthrie of Guthrie was Armour-Bearer to King James III of Scotland and the Sheriff of Forfar; he became Lord Treasurer of Scotland in 1461 and continued in this office until 1467, when he was appointed Comptroller of the Exchequer.
Split into simpler sentences: In 1457, Sir David Guthrie of Guthrie was armor bearer to King James III of Scotland, and the Sheriff of Forfar. In 1461, he became Lord Treasurer of Scotland, and in 1467, was appointed Comptroller of the Exchequer.