The Advanced Guard
“Fabius, the saviour of Rome, used to say that a commander could not make a more disgraceful excuse than to plead, ‘I never expected it.’ It is, in truth, a most shameful reason for any soldier to urge. Imagine everything, expect everything.”—SENECA, “De Ira.”
Every moving body of troops must be protected by detachments, the force detached to precede the advance being known as an Advanced Guard, and when a body of troops so protected halts, the responsibility for protection during the halts remains with the troops which have been protecting the march until they are relieved, the commander of the Advanced Guard exercising his discretion as to halting at once or moving forward to occupy a position which may be of more tactical advantage.
STRENGTH.—The strength of this Guard depends on the proximity of the enemy, but it must always be strong enough to brush aside slight opposition, so that the advance of the force it is covering may not be delayed by small hostile forces, and to resist the enemy, when encountered in strength, for such time as will enable the force it is covering to prepare to meet or deliver an attack. No general rule as to the numerical strength of an Advanced Guard can be given, as the number of troops required depends almost entirely upon the tactical situation and the country through which the protected force is passing. It should, however, whenever possible be composed of a complete unit or formation under its own commander, and it is found in practice that an Advanced Guard will seldom be less than one-eighth or more than a quarter of the whole force. When a large force is advancing in several columns on parallel roads it will be preceded by a “Strategical Advanced Guard,” which protects the front and flanks of all the columns. The “Tactical Advanced Guard” provided by each column may then be reduced in strength.
DISTANCE.—The distance at which it moves ahead of the force it is covering depends upon the nature of the country through which the force is moving, upon the strength of the Main Body, and upon the tactical situation, but it must always be sufficient to enable the Main Body to deploy, to get into battle formation—unmolested by the enemy’s artillery, if required to do so. It is clear, therefore, that the larger the Main Body the greater the distance must be, as more time will be required for deployment. The Advanced Guard of a Brigade of infantry, with artillery, would move at a distance of 1 to 2 miles between the Main Guard and the Main Body, with the mounted patrols of the Vanguard 4 to 5 miles ahead of the Main Body. These mounted patrols would discover the presence of an enemy, and with the supports of the Vanguard would feel for his strength and ascertain his dispositions. The Main Guard would either assist in brushing him away or would resist, in the best available position, any attempts to attack the Main Body while the latter formed up for battle.
IN ADVANCES.—Infantry forming part of an Advanced Guard to a force advancing must always act with dash and resolution, but their action must always be regulated by the one motive of complying with the intentions of the commander of the force they are covering. Any action contemplated by the Advanced Guard commander must therefore be considered from the point of view of its effects upon the plans of the commander of the main body, but if these plans are not known, the guiding principle will be to regulate his action solely in the interests of the force he is covering, and by driving in the advanced troops of the enemy he will obtain information which will assist his superior in coming to a decision, without interfering with his liberty of action, whereas hesitation and delay may give the initiative to the enemy. For this reason, a wide turning movement by the Advanced Guard troops is seldom possible, as time is thereby lost and the front of the Main Body is uncovered. “The ruling factor should be the discovery of some tactical locality held by the enemy, the capture of which will compel his whole line to fall back. If this point can be discovered the whole energies of the Advanced Guard should be directed against it alone, and elsewhere a defensive attitude should be adopted, to avoid surprise of or interference with the Main Body” (General R. C. B. Haking).
It must always be assumed that the enemy will have taken all the necessary steps to protect himself and to hamper reconnaissance by an adversary. If, therefore, hostile troops are known to be in a certain locality, opposition must be expected before that locality is reached, and study of the map should enable the Advanced Guard commander to determine the approximate neighbourhood in which opposition may be expected.
IN RETREATS.—While it is clear that a force advancing towards the enemy must always be preceded by an Advanced Guard it must not be forgotten that a force withdrawing from the enemy must also be so protected, even when it is moving in or towards friendly territory. Such a force will not only prevent the Main Body being surprised by an energetic enemy, pursuing swiftly and getting round to attack where he is least expected, but will also prevent the Main Body being delayed by obstacles, and can delay the pursuit by preparing bridges, etc., for demolition, which can be completed by the Rear Guard when the Main Body has passed over them. It can also reconnoitre the route to be followed, so that the Main Body can proceed without delay.
TRAINING.—In formulating any scheme for the exercise of troops in Advanced Guard work all officers and other ranks should be made to understand the nature of the scheme, and should be informed (a) whether the force is advancing or retreating, whether it is moving before or after action with the enemy, and whether it is in a friendly or a hostile country; (b) what is known of the enemy; (c) the direction and objective of the march; (d) the general intentions of the commander of the Main Body; and (e) the general instructions issued to the commander of the Advanced Guard. “Unless such exercises are carried out in a practical manner, young officers and inexperienced N.C.O.’s will get the impression that an Advanced Guard consists merely of a procession of small bodies of infantry, strung out at fixed intervals on a single road. It is of the highest importance that the training should be carried out on the lines that would be adopted in action” (G.H.Q. Circular).
TACTICAL PRINCIPLES.—“Speed of advance is the first consideration when not in contact with the enemy. Hence an Advanced Guard will move on a narrow front along roads and other channels of communication, with such distances between advanced and supporting bodies as to avoid possibility of surprise. When in contact with, or in the vicinity of, the enemy, security and speed of advance are equal considerations. Hence the Advanced Guard should move by bounds on a broad fighting front across country” (“Infantry Training, 1921”).
Before an Advanced Guard commander moves off in compliance with his instructions he will take certain steps in accordance with these tactical principles. He will divide his troops into two portions, known as the Vanguard and the Main Guard, and as the duties of the Vanguard are reconnaissance in general, as well as the protection in particular of the Main Guard, it will contain a large proportion of mobile troops, with infantry for assault and resistance, and engineers for clearing the way through or over obstacles. Aircraft, in advance of the Vanguard, not only increase the area under search and expedite the discovery of the enemy, but prevent surprise and assist the Advanced Guard as a whole by close co-operation in feeling for and fighting the enemy when encountered. “In order to reconnoitre one must compel the enemy to show himself wherever he may be. To this end he has to be attacked until the extent of his position has been clearly defined. But the attack is made with the intention not to bring on an action. The skirmishing lines will advance, but they must be able to disengage themselves at a given moment. Pressure is exercised from a distance without allowing the forces exerting that pressure to become tied up” (Marshal Foch). The duty of the Main Guard is Resistance, that is to say, fighting. It will therefore consist mainly of infantry, with artillery and machine guns, and the troops will move in the order in which they will come into action. The Vanguard will be preceded by scouts, special attention being paid to roads and tracks parallel with the advance. This screen is followed by the remainder of the Vanguard, in collected formation, until it is in contact with or in the vicinity of the enemy, with protection at all times against local surprise. The Main Guard follows, in touch with the Vanguard, and with local protection. Both portions have definite commanders, and the commander of the whole Advanced Guard will probably move with the supports of the Vanguard. The commander will also determine the relative distances between the Vanguard and the Main Guard, these being regulated by the strength of the Advanced Guard, and being based upon the necessity of one part supporting the other. The distance of the Advanced Guard ahead of the Main Body may have been mentioned in the operation orders, but if it is left to the discretion of the Advanced Guard commander he will be guided solely by the interests of the force he is covering, and his decision will be influenced by the nature of the country (whether it is open, or intersected by woods, hedges, sunken roads, etc., which make observation even by aircraft a matter of great difficulty) and by the tactical situation, such distance being chosen as will suit these conditions, while admitting the fulfilment of the objects in view, viz.:—to obtain information concerning the enemy and to prevent hostile reconnaissance; to prevent surprise and delay; and to enable the Main Body to deploy into battle formation without interruption by the enemy’s fire.
It is also the duty of the commander to ensure communication between the various parts of the Advanced Guard and between that force and the Main Body, by arranging for mounted orderlies and cyclists, signallers and connecting files, in addition to the contact patrols furnished by the Air Service, and to such telegraphic and telephonic communication as can be provided in the field by the Signals. This is of the first importance, as the action of the commanders of the Advanced Guard and of the Main Body will depend on information received, and not only must information be gained by every available means, but it must also be communicated without delay to all concerned while it is fresh and before it becomes stale. It must also be remembered that negative information (e.g. that such and such a village has been thoroughly searched and no trace of the enemy found) is at least of equal value to positive information. The repetition or confirmation of information already sent are also of importance, as it is clearly of value to a commander to know positively that the enemy is still absent, or still present, at a certain time in a certain locality. In the American Civil War, during an encounter battle between advanced troops, the commander of the cavalry of the United States Army held up the Confederate advanced troops. A sharp fight took place at Sulphur Springs (October 12, 1863) and the United States cavalry commander became so absorbed in the battle that he failed to send information to headquarters, and General Meade did not learn that he was in contact with the Army of Northern Virginia until late in the afternoon. In the campaign of Fredericksburg, General R. E. Lee, with the Army of Northern Virginia, was confronted by General Burnside, with the Army of the Potomac. On November 15, 1862, a patrol of Confederate cavalry discovered Burnside’s troops moving eastwards, and another patrol brought news the same day that gunboats and transports had entered Acguia Creek on the Potomac. These two pieces of information, collected at points 40 miles distant from one another, gave Lee an insight into his opponent’s design. Information gained by aircraft on September 4 and 5, 1914, and communicated immediately to General Joffre, led to the discovery of the flank march across the Franco-British front by the German I. Army, and to the decisive counter-attack at the First Battle of the Marne (September 6, 1914).
The Advanced Guard commander must be careful how he becomes seriously engaged, and must avoid any enterprise not strictly in accordance with the known intentions of the commander of the Main Body. The tendency to independent action of this kind, which militates against the success of the best laid plans, was very observable in the early battles of the Franco-Prussian War of 1870-1871. Actions were hastily entered on by Advanced Guards, maintained with varying success by the gradual arrival of reinforcements, and finally concluded with barren results and losses in excess of those inflicted. At the Battle of Spicheren (August 6, 1870) the Advanced Guard of the 14th Prussian Division commenced the battle, which had to be sustained for three hours by 11 battalions against 39. During the next three hours 8 more battalions arrived, and at the conclusion of the battle only 27 battalions and 10 batteries in all had come into action against a whole French Corps, and there were two French Corps within reach of the one engaged. Had these “marched to the sound of the cannon,” as Napoleon would have marched, the 14th Prussian Division would have been unable to extricate itself without complete disaster. At the Battle of Worth (August 6, 1870) the Prussian Crown Prince had expressed his intention not to engage the French on that day. Yet the Advanced Guard of the V. Corps brought on a battle into which the Bavarian Corps was perforce drawn. The Crown Prince sent word for the action to be discontinued, but the advanced troops were so seriously involved in the battle that reinforcements had to be sent into action. Although tactically successful the battle was out of accord with the settled plans of the Commander-in-Chief. In the same way the Advanced Guard of the VII. Prussian Corps, contrary to the letter and the spirit of the orders of the commander of the I. Army, precipitated an action at Colombey (August 14, 1870). Other troops were drawn into the fight, and finally the whole of the I. Army was engaged in a battle which its commander not only disapproved but had expressly forbidden. The battle had no tactical or strategical results, and heavy losses were sustained on both sides. “Precipitate action of this kind prevents the troops being engaged in the most advantageous manner. For when a small force is engaged against a larger one it becomes necessary, as reinforcements arrive, to move them up to support some point already hard pressed, and the whole force is thus used up and disseminated, instead of being employed collectively where an effective blow may be struck. Thus the direction of the fight is surrendered to the enemy, as at Spicheren and Colombey. The French positions were so strong that the German reinforcements as they arrived were frittered away in support of troops already engaged, and the state of the latter during the action was frequently very critical. At Colombey the battle resolved itself into a desperate struggle along the front of the French position, where the Prussians made little impression, while their losses considerably exceeded those inflicted on the French” (Clery). It is thus seen that the commander of the Advanced Guard must limit his aggressive action in accordance with his instructions and with the tactical and strategical requirements of the force he is covering. But his action in protecting the Main Body is unfettered by any considerations of prudence, and must ever be vigorous and resolute, any risks being taken that ensure the safety of the Main Body. On the morning of the Battle of Nachod (June 27, 1866) the Advanced Guard of General Steinmetz’s V. Corps (of the Army of the Crown Prince of Prussia) was in bivouacs on a plateau, after emerging from a long and narrow defile through which the Main Body must march to the open country beyond. About 8 a.m. the cavalry of the Vanguard was checked by the advanced troops of the VI. Austrian Corps. It was imperative that the Prussian Advanced Guard should hold the plateau until the Main Body had extricated itself from the defile. By the rapid and accurate fire of the infantry and horse artillery, and the co-operation of the cavalry against the Austrian squadrons, the thin line was maintained for more than three hours. Less than 7 battalions of infantry, with 13 squadrons of cavalry and 3 batteries of light artillery, kept in check 21 battalions, 11 squadrons, and 4 batteries. Had the Advanced Guard suffered itself to be driven back on the Main Body in the defile a disaster could scarcely have been avoided, and owing to the steadfast endurance of the Advanced Guard the Main Body was able to drive the Austrian Corps from the field.
ADVANCED GUARD PROBLEMS.—The Advanced Guard commander must be able to appreciate without delay the situation which confronts his force, and to solve the problem before him with regard solely to the interests of the force he is covering.
(a) If the Vanguard is held up by the enemy who is ascertained to be inferior in strength to the Advanced Guard, the commander will transmit information to the Main Body and will attack vigorously to disperse the enemy, in order that the movements of the Main Body may not be delayed. A fire attack would be organised on the front of the enemy, supported by close-range artillery fire, and a turning movement with Lewis guns and rifles on one or both flanks. If the enemy held to a covered position they could be ejected by rifle bombers or light mortars from a flank, while artillery and machine guns prevented aimed fire at the attacking force.
(b) If fire is opened on the Vanguard and definite information as to the strength and dispositions of the enemy cannot be ascertained, such information as had been gained would be transmitted and a bold procedure would be adopted in order that the information might be supplemented as quickly as possible. The commander would reinforce his Vanguard with infantry from the Main Guard, and should be able to force the enemy to disclose his position and strength, but unless ordered to do so would take care not to become so involved in action that the Main Body would be compelled to come up and extricate them.
(c) If the enemy is encountered when the Advanced Guard commander knows that it is the intention of his superior to deliver an attack the information would be transmitted with an outline of the steps taken in seizing and securing all tactical points that will be of service to the Main Body. The Advanced Guard would work on a wider front than would otherwise be used by a force of that strength, and the artillery would be posted with a view to its position being adopted as the main artillery position.
(d) If, under similar circumstances, the intention not to be drawn into a decisive engagement is known by the Advanced Guard commander he would limit his activities to reconnaissance of the enemy’s position and numbers, and while hampering the enemy and preventing him from finding out particulars concerning the Main Body, he must take care not to become involved in a general engagement.
(e) A case may easily occur in which vigorous action is demanded, whether the commander of the Main Body intends to attack at once or to defer an engagement. Such a situation would arise if the Vanguard discovered the approach of the enemy towards a ridge or other position of tactical advantage, and if the Advanced Guard commander could, by a rapid advance, forestall the enemy in the occupation of such a position, his failure to do so, or hesitation in waiting for explicit orders to do so, would be a grave neglect of duty.
(f) In the American Civil War a tactical blunder of another kind, due to the impetuosity of the commander of the Independent Cavalry of the Army of Northern Virginia, prevented the Southern commander from obtaining a great strategical advantage over the Army of the Potomac. The latter force had been withdrawn by General McClellan, after the Seven Days’ Battle around Richmond, to a secure position at Malvern Hill, where the assaults of the Army of Northern Virginia were beaten back with heavy losses. McClellan continued the withdrawal and had reached Harrison’s Landing on the James River. The Independent Cavalry of the Southern Army had previously been dispatched on a false scent, but at 9 a.m. on July 3 touch was regained with the Northern forces, which were sighted from Evelington Heights (July 3, 1862), a commanding ridge within two miles of the bivouacs of the Army of the Potomac, which was resting in apparent security, with inadequate precautions against surprise. General J. E. B. Stuart, the Confederate cavalry commander, reached Evelington Heights with 1,200 sabres and carbines and one light howitzer, and the whole Army of the Potomac, 90,000 all arms, was in bivouacs in full view from the Heights, and it was clear that his presence was not suspected. The nearest column of the force he was covering was six miles away, and there remained about ten hours of daylight. It is easy to see, after the event, that this was a case where “Silence is golden.” Stuart should have sent the information to Lee and to every column commander, urging them to press on at all speed, while he occupied the Heights with his dismounted men with the determination to hold his position with fire action, if discovered, until the arrival of one or more columns of the Army of Northern Virginia. But he failed to appreciate the situation, and forgetting the larger question, he seized the opportunity to spread panic in the ranks of the Army of the Potomac, and opened fire with his one light howitzer. The Northerners recovered from the panic caused by this unexpected attack, when it was realised that only one gun was in action against them, and attacked and captured the Heights, and were strongly entrenched there before the nearest Confederate column arrived.
(g) Among the examples of Advanced Guard work in Marshal Foch’s “Principles of War” is a problem for a battalion as the Advanced Guard of a Brigade. “What is the problem the battalion commander has to solve? It consists in preparing for the brigade to go into action against an enemy who may debouch from Bettwiller. What does the brigade require for such an action? It requires the space necessary for the full employment of its forces, and the time necessary for their arrival and deployment. In order to achieve that double task the battalion commander orders his troops to occupy the whole space necessary, and places them in points where they may hold on for the necessary time.”