The period in question began quietly with the Luftwaffe busy elsewhere, yet the increasing attacks on Germany by the Royal Air Force provoked a response in the form of the so-called Baedeker offensive of 1942. And it is against the background of the hammer blows dealt out to German towns and cities that the Blitz on Britain during the 1942–1944 period must be viewed. Hitler’s ­frustration at not being able to hit back, like for like, led to the appointment in 1943 of a Blitz ­supremo to mete out retaliation. This finally came in 1944 with the Steinbock raids — known better as the Baby Blitz — yet it was only an interim measure. As the manned bomber attacks faded, so a new and fearsome method of attack by robot bomb began with weapons of vengeance. The V1 and V2 period is fully documented with the basic facts and figures ­balanced by eyewitness accounts never before published.   The three volumes of The Blitz Then and Now run to more than 1,500 pages and include over 3,500 ­illustrations. It has taken ten years to bring to fruition — longer than the period it encompasses — and it is dedicated to the 60,000 British civilians who died and the 86,000 who were injured.