Baron Clitheroe of Downham in the County of Lancaster is a title in the Peerage of the United Kingdom. It was created in 1955 for the Conservative politician Ralph Assheton, who had previously served as Financial Secretary to the Treasury. He was the son of Ralph Cockayne Assheton, for many years a member of the Lancashire County Council, who had been created baronet of Downham in the County of Lancaster, on 4 September 1945. Three months after being raised to the peerage, Lord Clitheroe succeeded his father in the baronetcy. As of 2010[update], the titles are held by the first Baron's son, the second Baron, who succeeded in 1984.
In the immediate aftermath of World War II, Ralph Assheton also acquired title to manorial and mineral rights as well as land holdings within the former Honor of Clitheroe. These were purchased out of the Clitheroe Estate Company following its administration in 1945. They included the Lordship of the Forest of Pendle. The Clitheroes' land agent, Michael Parkinson of Ingham & Yorke, continues to style himself "Steward of the Honor of Clitheroe". Parkinson is also "Chief Steward of the Forest of Bowland".
Assheton baronets of Downham (1945)
- Sir Ralph Cockayne Assheton, 1st Baronet (1860–1955)
- Sir Ralph Assheton, 2nd Baronet (1901–1984) (had been created Baron Clitheroe in 1955)
Barons Clitheroe (1955)
- Ralph Assheton, 1st Baron Clitheroe (1901–1984)
- Ralph John Assheton, 2nd Baron Clitheroe (born 1929)
The heir apparent is the present holder's son Hon. Ralph Christopher Assheton (born 1962)