Arthur John Brereton Marwick (1936-2006) was a Scottish social historian, who served for many years as Professor of History at the Open University. His research interests lay primarily in the history of Britain in the twentieth century, and the relationship between war and social change.
An effective overview of the debates about whether or not a 'Blitz spirit' united Britain, or whether class society still prevailed (Marwick leans a little towards the former, but I'm with Angus Calder on this). What makes the book particularly useful, particularly with students, is its integration of a wide array of photos from the period, many of which were censored at the time, as well as a spattering of Mass Observation diaries.