Educated at Burton on Trent Grammar School and Durham University. During the First World War he enlisted in the York and Lancaster Regiment on the 24th September 1915 as a temporary Second Lieutenant. He was awarded the Military Cross in recognition for his gallantry and devotion to duty by making frequent reconnaissances under heavy fire, as Battalion Intelligence Officer.

After the war he continued his studies and joined Metropolitan-Vickers Electrical Co Ltd as a college apprentice from 1921 to 1922. He worked in the electrical and magnetic section of the Research and Education Department of the company and eventually was put in charge of the section.

In 1936 he was awarded a PhD by Durham University, a little later in 1938 he became a part-time lecturer at Queen Mary College, University of London. He held the chair for Electrical Engineering at the University of Birmingham however, he did continue to work for Metro-Vicks as well. At the outbreak of the Second World War he worked for the Admiralty and because of this work was awarded the O.B.E. for work related to naval gunnery.

In 1944 he returned to work at Metro-Vicks and became Director and Chief Electrical Engineer in 1947. He was to eventually become a Director of Associated Electrical Industries in 1954. On the 7th February 1961 the Queen Mother conferred the title of Sir Cecil Dannatt at a ceremony held at Buckingham Palace.