The Area Bombing Directive was a directive from the wartime British Government's Air Ministry to the Royal Air Force which ordered RAF bombers to attack the German industrial workforce and the morale of the German populace through bombing German cities and their civilian inhabitants.
The Area Bombing Directive (General Directive No.5 (S.46368/111. D.C.A.S) was a 14 February 1942 amendment to General Directive No.4 (S.46368 D.C.A.S), issued by the British Air Ministry on 5 February 1942, that had informed RAF Bomber Command that it had "Priority over all other commitments", and directed RAF Bomber Command to bomb factories in occupied France. General Directive Number 5 amended Number 4 to make targets in Germany the priority for RAF Bomber Command.
The directive issued on 14 February (S.46368/111. D.C.A.S) listed the primary industrial areas that were within 350 miles from RAF Mildenhall; the distance being a little over the maximum range of the GEE radio navigation aid (referred to in the directive as "T.R. 1335"). The directive specifically mentions the Ruhr and that Essen, in the centre of the conurbation was to be given the dubious honour as the first target that was to be bombed (the first attack on Essen under this directive was carried out on the night of 8/9 March). The objective of the directive was "To focus attacks on the morale of the enemy civil population and in particular the industrial workers. In the case of Berlin harassing attacks to maintain fear of raids and to impose A. R. P. measures".
The directive issued on 14 February listed the north coast industrial areas (within range of GEE) and industrial areas beyond the operational reach of GEE (Berlin by name and northern central and southern Germany), as secondary targets to be bombed when the weather over those targets was more suitable for bombing than over the primary area. Other German cities mentioned by name and to be attacked with a high-explosives were Duisburg, Düsseldorf and Cologne. Billancourt in occupied France, that was the primary target in the directive issued on 5 February (Air Ministry Reference 46268 D.C.A.S) and immediately preceding this one, was to become secondary target (it was bombed on the night 3/4 March). In addition the RAF were also directed to carry out specific operations to support Combined Operations, such as the periodic bombardment of targets of immediate strategic importance, for example naval units (see Channel Dash that happened only 2 days before this directive was issued), but it added a qualifier that these were only to be carried out if good opportunities to attack primary targets were not missed.