Lindemann became a professor of experimental philosophy (physics) at Oxford in April 1919 and later helped to rebuild its Clarendon Laboratory. He first met Churchill in August 1921 and soon was a regular visitor to Churchill's residence, Chartwell Manor, in Kent, becoming friends with the whole Churchill family, thanks in part to his ability to explain abstruse scientific facts or theories in language that could be understood by a layperson.
Lindemann entered government as Churchill's adviser at the Admiralty in September 1939. A month later, he established a statistical section. In 1942, he was named paymaster general, a cabinet position that he held until 1945. But his primary focus was on advising Churchill (in the course of the war, he sent the prime minister some 2,000 memos, about a third of them concerned with weapons or the armed forces) and heading the Statistical Branch, which reduced as many aspects of the conflict as possible to quantitative terms to allow easier assessment of what was working and what was not.
Arguing from the data developed by his statisticians, Lindemann strongly supported strategic bombing (though he deliberately overestimated its likely impact), and he backed development of the proximity fuse. Unfortunately, he retained grudges, had an acidic personality, appeared aloof (with his obstinate nature, he did not suffer fools well), offered opinions on subjects about which he was not an authority, and was all too easily critical of others, which did not endear him to those around him.
Lindemann was named a peer in 1941, becoming Lord Cherwell (after the river in Oxford), and was made a viscount in 1956. He taught at Oxford after the war and then briefly joined Churchill's second government, until he resigned due to ill health (in October 1953) and returned to Oxford. He died there on 3 July 1957.
Christopher H. Sterling
Earl of Birkenhead. The Professor and the Prime Minister: The Official Life of Professor F. A. Lindemann, Viscount Cherwell. Boston: Houghton Mifflin, 1962.; Harrod, R. F. The Prof: A Personal Memoir of Lord Cherwell. London: Macmillan, 1959.; Wilson, Thomas. Churchill and the Prof. London: Cassell, 1995.