This book, published in 1980, explores British computing from the 1930s to the 1960s, covering both technical and general historical aspects of the story.

From the blurb:

'Much of the pioneering work on modern computers took place in Britain between 1945 and 1955, including such landmarks as the world's first stored-program computer, the first commercially available computer, and the first transistorised computer.  This book tells the story of these and other machines and their designers.  Beginning with a survey of computing in the 1930s, it includes secret wartime developments, post-war research in universities and government establishments, and the work of companies such as Elliott Brothers, English Electric, Ferranti and Lyons in the 1950s.  From here the growth of an indigenous computer industry is traced up to the period of merger and consolidation in the early 1960s.  Contemporary American developments highlight the interplay of ideas on both sides of the Atlantic.'

Chapter 13, pages 68-77, gives a brief history of LEO and English Electric, including a timeline.