Sir James Frederick Rees (13 December 1883 – 7 January 1967), known as Frederick Rees, was a Welsh historian and academic born in Milford Haven, who specialised in economic history and the history of Wales. From 1929 to 1949, he was Principal of University College of South Wales and Monmouthshire. He was additionally Vice-Chancellor of the University of Wales from 1935 to 1937 and also from 1944 to 1946. He had previously lectured at University College, Bangor, Queen's University Belfast, the University of Edinburgh, and the University of Birmingham.^[1][2][3] He served as High Sheriff of Pembrokeshire for 1955.^[4]

In the 1945 New Year Honours, Rees was appointed a Knight Bachelor, and thereby granted the title sir, in recognition of his service as Principal of the University College of South Wales and Monmouthshire, Cardiff and as Vice-Chancellor of the University of Wales.^[5] He was knighted by King George VI during a ceremony at Buckingham Palace.^[6]

• J. F. Rees (1920). A Social & Industrial History of England, 1815-1918. London: Methuen & Company Limited.
• —— (1921). A Short Fiscal and Financial History of England, 1815-1918. London: Methuen & Company Limited.
• —— (1933). A Survey of Economic Development: With Special Reference to Great Britain. London: Sir I. Pitman & Sons, Limited.
• —— (1954). The Story of Milford: (Milford Haven). Cardiff: University of Wales Press.
• —— (1963). The Problem of Wales: And Other Essays. Cardiff: University of Wales Press. ISBN 978-0708300695.
• —— (1965). Studies in Welsh History Collected papers, lectures and reviews (Second ed.). Cardiff: University of Wales Press.