GHQ operating Instruction No 1 (June 1940) stated that “Defences wherever possible will be of concrete construction and provided with overhead cover”. It further stated that beaches selected for defence would be protected by light machine guns in pillboxes and that beach exits would be mined and protected by pillboxes. GHQ Operating Instruction No 3, detailing Ironside’s defence plan for Britain, outlined the role of inland Stop Lines where the anti-tank obstacle was to be protected by anti-tank guns and light machine guns housed in pillboxes.
The Defence scheme for 11 Corps, also notes the use of pillboxes for beach defence – “maximum use being made of concrete pill-boxes to house anti-tank rifles and light automatics”.
The reliance on static defences in 1940 was a result of the general lack of training of the majority of troops detailed to hold the beaches, especially in mobile warfare, and the paucity of equipment. These troops were expected to hold to the last, with no question of withdrawal, by doing so they would disrupt the enemy and allow mobile forces to move forward to counter attack.
The advantages of concrete defences were highlighted in two GHQ memos. A memo dated Oct 1940 details the advantages of concrete works over other Field works. Many places where defences were required were exposed to the weather or in places which would be left for occupation where normally few troops were stationed and hence maintenance difficult. Many defence works would have to be erected near or among buildings where a concrete structure would be less conspicuous and easy to camouflage.
Another memo dated Nov 1940 notes that “From a tactical point of view, the basis of organization of beach defences against invasion is generally to house all guns and L.M.Gs in concrete works.” The memo also notes that Field works are also essential as the limitation of concrete defences is a limited field of fire and difficultly in ensuring all round defence. Due to the problems of constructing field works in sandy soils and their exposure to the weather, as noted in the earlier memo, it was considered necessary that defences against invasion should consist of both concrete and field works.
The scale of construction of pillboxes in Eastern Command can be gauged by the following memo from Eastern Command to GHQ dated 17th July 1940 which detailed the state of construction of the defences in the Command’s area:
In Suffolk, during the summer of 1940, there appears to have been little coordination or thought in the siting of defences. Major General Majendie, commanding 55th Div highlighted this in his memo “Pill-box Complex” dated Aug 5th 1940:
“I am very much afraid that we are going pill-box mad, and losing all sense of proportion in the matter of siting defences. The lure of concrete is leading us away from first principles. The countryside is covered with pill-boxes, many of which will never be occupied, many could never serve any useful purpose, and many face the wrong way. Much labour, money and material have been wasted. I realise that this is largely due to haste and the desire to get something done quickly”.
The 125th Brigade (42nd Div which relieved 55th Div in Nov 1940) notes that “the defences are linear all down the beach, and they just “happened”. The 55 Div stuck pillboxes…….just where they wanted them”. Lt Col Ovey, D.S.O. notes that inland “pill boxes began to spring up at cross roads and road junctions often in the most obvious and vulnerable positions………I have no idea who was responsible for their sightings as no reference was ever made to the local Home Guard Commanders or as far as I know to any regular military Commander!”
Major General Majendie continues in his memo to outline the limitations of the pillbox and how it should be used tactically. He points out that a defensive position should have an adequate field of fire and allow the maximum volume of fire to be delivered. If the garrison was in a pillbox, only two weapons could be fired in one direction leaving the rest of the garrison unable to take part (unless of course in the pillbox was being assaulted on all sides simultaneously). He stated that the pillbox should be regarded as a keep in a defended locality in which the garrison could take cover during air attack by bombs or machine guns. As soon as the air attack ceased or enemy troops approached the greater part of the garrison was to leave the pillbox and fight from trenches adjoining the pillbox, allowing all the weapons of the garrison to be fired simultaneously in any one direction. In essence the pillbox could not be regarded as a suitable defensive post on its own but rather should be part of a small defended locality.
Infantry Training 1937, Supplement No 1 – tactical Notes for Platoon Commanders 1941 makes the same point as Major General Majendie:
“A Post in Concrete
(1) The concrete pill box is a great aid to defence if intelligently used: if not, it may become a death-trap.
(2) Concrete is a protection against bullets, shell splinters, and weather. Sometimes it affords protection against shell fire. If properly camouflaged, it is also a protection from ground and air observation.
(3) Many concrete posts are not complete protection against a direct hit from as shell or from an aerial bomb. They all have the disadvantage of limiting the field of view and the field of fire. The garrison will be unable to use all their rifles at one and the same time because of the fewness of the loopholes. Finally, the garrison is hindered in the employment of the hand grenade and bayonet.
(4) Therefore the garrison of a pill box locality will act as follows:-
(a) The sentry or sentries on duty will be stationed outside the pill box, where they can see and hear all round them.
(b) Temporary cover from view, shell fire, and aerial bombing may be sought inside the pill box; but beware that the enemy are not creeping towards you under this covering fire, whilst you are hiding inside.
(c) When the attack comes, the light machine gun or machine gun will fire from the pill box, if it can carry out its task, If not, it must come out to a prepared position.
(d) Those men who cannot use their weapons inside must man the trenches outside – where they can do their duty.
(e) If the pill box is surrounded – except for those who can fire from the loopholes, the garrison will fight outside, where they can employ all their weapons to the best advantage.”
Senior military Commanders were unhappy with reliance of static concrete defences and were concerned that a “Maginot Line” mentality may develop amongst troops. The pamphlet The Officer and Fighting Efficiency makes this point: “Troops must not be led into battle in the belief that the “prepared positions” to the rear exist primarily to offer them refuge in the face of a determined enemy. Over-reliance on static defensive measures and concrete fortifications will kill the fighting spirit of any army….”. The 42nd Div Defence Scheme (front line Div in suffolk Nov 1940 to Feb 1941) notes that " There is a tendency to become pillbox minded. Pillboxes are often sited in the ideal postion for a German M.G to fire on them. Atthough the pillbox is bullet proof it may often be better to occupy a house in line with the pillbox, and mislead the enemy into thinking fire is comming from the pillbox. This is particularly the case where the pillbox is obvious or is situted in line with a German gun firing on the move down a road".
Caution on the reliance of pillboxes was also given in Home Guard training which noted that pillboxes “should only be used now if:-
(a) They can be completely concealed.
(b) They are fire-proof against anything but heavy tank gun fire.
(c) The loopholes give complete and all-round fields of fire.
Even then they do not make for an aggressive defence so can only form part of the squad defences. Communication from inside to those outside is difficult so that control is lost. Weigh carefully their advantages and disadvantages before you keep them in your defence plan. Don’t man them just because they are there.”
It was also recommended to the Home Guard they consider using pillboxes constructed as part of a road block as “dummy positions” to draw fire away from the actual positions.
Throughout 1941 pillboxes were still an important part of defence schemes although to be used tactically as outlined in the 1941 Supplement to Infantry Training. In the spring of 1941 a new machine gun mounting was approved – the Turnbull Mount. This consisted of a frame, a cradle and Gun bar. The frame was embedded in a loophole of a pillbox while the cradle allowed the machine gun to pivot and elevate or depress. A specifically designed Gun bar could hold either a Vickers, Bren, Browning or Lewis machine gun. The cradle would permit a traverse of 90° and elevation of 11.5° and a depression of 12°. The mounting allowed the machine gun to be fired on a traversing arc or laid on a fixed line.
Top left: Turnbull Mount frame that has been mounted in a WW1 Pillbox. Bottom left: Frame & Gun bar
Right: Plan of the Turnbull Mount frame.
It was recognized that many pillboxes would never be occupied either due to being sited in inappropriate positions or insufficient troops. All pillboxes, either inland or for beach defence which Commanders did not intend to occupy were to be rendered harmless either by blocking the embrasures with cement/bricks or filling with wire. The exception to this was pillboxes on the Stop Lines which were to be maintained so they could be occupied by relieving or reinforcing troops ordered to keep the line.
By 1942 the pillbox was seen redundant as a defence work. A GHQ memo, “Construction of Field Defences” , Feb 23rd 1942 notes: “All experience of modern warfare…..points most strongly to the fact that the pillbox is not a suitable type of fortification for either coastal or nodal point defences.” The memo highlights that to be proof against modern weapons needs a great thickness of reinforced concrete which makes concealment difficult as well as severely reducing the arc of fire or requiring dangerously wide loopholes. All new Field defences were to now consist of well sited earthworks capable of all round defence. It was recognized that many pillboxes occupied the best firing positions – these could be retained in defence schemes but alternative earthwork positions would have to be provided.
55th Div papers, TNA
125 Brigade papers, TNA
Pillboxes Jun 1940-Dec 1941, TNA
The Officer and Fighting Efficiency 1940, War Office, Feb 1941
Infantry Training, 1937 Supplement No 1. Tactical Notes for Platoon Commanders, War Office , Oct 1941
Home Guard Instruction No 51, Part IV The Organization of Home Guard Defence, GHQ Home Forces, Nov 1943