Denys Hay was a historian

Historian

A historian is a person who studies and writes about the past and is regarded as an authority on it. Historians are concerned with the continuous, methodical narrative and research of past events as relating to the human race; as well as the study of all history in time. If the individual is...

 specializing in medieval and Renaissance

Renaissance

The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...

 Europe, and notable for demonstrating the influence of Italy on events in the rest of the continent.

He taught at the University of Edinburgh

University of Edinburgh

The University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...

 from 1954, eventually becoming Professor of Medieval History until he retired in 1980, and is remembered with the "Denys Hay Seminar" there.

Books

• The Anglica historia of Polydore Vergil, AD 1485-1537, editor (1950)
• Polydore Vergil: Renaissance Historian and Man of Letters (Clarendon Press, 1952)
• From Roman Empire to Renaissance Europe (1953), revised as The Medieval Centuries (1964)
• Europe: the Emergence of an Idea (Edinburgh University Press
  Edinburgh University Press
  Edinburgh University Press is a scholarly publisher of academic books and journals, based in Edinburgh, Scotland.-History:Edinburgh University Press was founded over 50 years ago and became a wholly owned subsidiary of the University of Edinburgh in 1992...
  
  , 1957)
• The Italian Renaissance in its Historical Background (1961, 1977)
• Europe in the Fourteenth and Fifteenth Centuries (1966, 2nd ed 1989) ISBN 0-582-49179-7
• Italian Clergy and Italian Culture in the Fifteenth Century (1973)
• Renaissance Essays (1988)
• Italy in the Age of the Renaissance, 1380-1530 (Longman History of Italy) (1989) ISBN 0-582-48359-X
• New Cambridge Modern History, volume 1 (1957), ed.
• Annalists and historians : Western historiography from the eighth to the eighteenth centuries (1977)