Donald Elmslie Robertson Watt FRSE (15 August 1926 – 18 April 2004) was a Scottish historian and Professor Emeritus at St Andrews University.
He graduated in 1950, and moved to Oriel College, Oxford, receiving his D. Phil in 1957.
He worked for many years on editing and translating a nine volume edition, the first since 1759, of Abbot Walter Bower's Scotichronicon, a key resource for Scotland in the late Middle Ages.
Professor Watt also published on the Scottish church where he was the acknowledged expert on sources, holding the chair in Scottish Church History at St Andrews.
He worked for the publication of the Atlas of Scottish History, issued by the University of Edinburgh in 1975 and again, with revisions, in 1995.