The speed at which armies operate is a crucial factor in understanding their supply demands.
Written by Count Yegor Frantsevich Kankrin (Егор Францевич Канкрин) (16 November 1774 – 10 September 1845) as a three volume set in 1820, it followed his service in the Russian Army as a Commissary during the Napoleonic Wars. In 1823, he was appointed Finance Minister, a post he would hold for the next 21 years, his most singular achievement being the reform of the Russian currency.
His book on military supply expands on Clausewitz's theme that armies can best live by requisitioning from the local authorities and can, in most circumstances live without magazine supply, which he considers limits the manoeuvrability of armies. However he goes further than Clausewitz, giving detailed statistics on the availability of supplies in seven categories of terrain from highly cultivated lands to desert, with examples of actual countries or provinces that correspond to these categories. Using these statistics and calculations on the supply requirement of a typical corps, he shows the method of supply needed for each of these terrain categories, highly cultivated terrain can support a corps by requisitioning and quartering, medium cultivated terrain is the same with the support of some magazine supply, lightly cultivated terrain requires magazine supply and limits the size of the army, while semi-desert and desert can only support small forces.
Bibliographic listing: Kankrin, Y. F. Uber Die Militairokonomie Im Frieden und Krieg, und Ihr Wechselverhaltniss zu den Operationen.
Krankrin's book is unclear as to the area of land required by his typical Corps for foraging in his seven categories of terrain and their associated population density. However Clausewitz does give an indication of the area of land needed to sustain a Corps of 30,000 men for a couple of days when the population density is 2,000-3,000 inhabitants per Q Meile (35-55 people per km sq) which is a square of 2 Q Meile sides (15 km) or an area of 4 Q Meile (225 km sq). By combining these two approaches it is possible to quantify Krankin's model.
|Number of troops sustained by certain levels of population density – Kankrin methodology|
|Population density inhabitants per Q Meile||Population density (inhabitants per km2)||Foraging square of 2 Q Meile (15 km2)||Countries 1820||Supply method|
|Area||4 QM or 225 km2|
|Medium cultivated||1,500||26||24,000||Poland||Requisition & Magazine|
|Medium cultivated||1,000||18||16,000||Spain||Requisition & Magazine|
|Little cultivated||800||14||12,800||Russia||Magazine supply|
|Semi-desert||300||5||4,800||Turkey||Unsuitable for large armies|
|Desert||150||3||2,400||Mountains||Short distances for small corps|
In his writings, Clausewitz identifies a number of key features of supply by horse-drawn armies, firstly that the balance of the types of units making up the army is important in determining their supply. Too much cavalry or artillery or baggage train reduces both the mobility of the army and the demand for fodder can overwhelm the supply service in various circumstances. Secondly he demonstrates that different types of supply have varying levels of administrative efficiency, while some are positively destructive, but the determining factor in which one to employ is the ability of the local area to provide the supplies. He even goes so far as to give us an estimate of the density of population required to support a Corps sized force for a few days. When Clausewitz refers to 'miles' he is using the Prussian mile of 7.5 km as his measurement, so he is referring to a population density of 35 to 55 inhabitants per km sq and the Corps needing an area of 225 km sq with sides of 15 km long.
1.—Living on the inhabitants, or on the community, which is the same thing.
"If we bear in mind that in a community consisting even as it does in great towns, of consumers only, there must always be provisions enough to last for several days, we may easily see that the most densely populated place can furnish food and quarters for a day for about as many troops as there are inhabitants, and for a less number of troops for several days without the necessity of any particular previous preparation. In towns of considerable size this gives a very satisfactory result, because it enables us to subsist a large force at one point. But in smaller towns, or even in villages, the supply would be far from sufficient; for a population of 3,000 or 4,000 in a square mile which would be large in such a space, would only suffice to feed 3,000 or 4,000 soldiers, and if the whole mass of troops is great they would have to be spread over such an extent of country at this rate as would hardly be consistent with other essential points. But in level countries, and even in small towns, the quantity of those kinds of provisions which are essential in war is generally much greater; the supply of bread which a peasant has is generally adequate to the consumption of his family for several, perhaps from eight to fourteen days; meat can be obtained daily, vegetable productions are generally forthcoming in sufficient quantity to last till the following crop. Therefore in quarters which have never been occupied there is no difficulty in subsisting troops three or four times the number of the inhabitants for several days, which again is a very satisfactory result. According to this, where the population is about 2,000 or 3,000 per square mile, and if no large town is included, a column of 30,000 would require about four square miles, which would be a length of side of two miles. Therefore for an army of 90,000, which we may reckon at about 75,000 combatants, if marching in three columns contiguous to each other, we should require to take up a front six miles in breadth in case three roads could be found within that breadth.
If several columns follow one another into these cantonments, then special measures must be adopted by the civil authorities, and in that way there can be no great difficulty in obtaining all that is required for a day or two more. Therefore if the above 90,000 are followed the day after by a like number, even these last would suffer no want; this makes up the large number of 150,000 combatants.
Forage for the horses occasions still less difficulty, as it neither requires grinding nor baking, and as there must be forage forthcoming in sufficient quantity to last the horses in the country until next harvest, therefore even where there is little stall-feeding, still there should be no want, only the deliveries of forage should certainly be demanded from the community at large, not from the inhabitants individually. Besides, it is supposed that some attention is, of course, paid to the nature of the country in making arrangements for a march, so as not to send cavalry mostly into places of commerce and manufactures, and into districts where there is no forage.
The conclusion to be drawn from this hasty glance is, therefore, that in a moderately populated country, that is, a country of from 2,000 to 3,000 souls per square mile, an army of 150,000 combatants may be subsisted by the inhabitants and community for one or two days within such a narrow space as will not interfere with its concentration for battle, that is, therefore, that such an army can be subsisted on a continuous march without magazines or other preparation."
"If circumstances are less favourable, if the population is not so great, or if it consists more of artisans than agriculturists, if the soil is bad, the country already several times overrun—then of course the results will fall short of what we have supposed. Still, we must remember that if the breadth of the front of a column is extended from two miles to three, we get a superficial extent of country more than double in size, that is, instead of four we command nine square miles, and that this is still an extent which in ordinary cases will always admit of concentration for action; we see therefore that even under unfavourable circumstances this method of subsistence will still be always compatible with a continuous march.
But if a halt of several days takes place, then great distress must ensue if preparations have not been made beforehand for such an event in other ways. Now these preparatory measures are of two kinds, and without them a considerable army even now cannot exist. The first is equipping the troops with a wagon train, by means of which bread or flour, as the most essential part of their subsistence, can be carried with them for a few, that is, for three or four days; if to this we add three or four days' rations which the soldier himself can carry, then we have provided what is most indispensable in the way of subsistence for eight days.
The second arrangement is that of a regular commissariat, which whenever there is a moment's halt gathers provisions from distant localities, so that at any moment we can pass over from the system of quartering on the inhabitants to a different system."
2.—Subsistence through exactions enforced by the troops themselves.
"The result is, therefore, that the subsistence of troops by forced contributions in this manner can only be adopted with success when the bodies of troops are not too large, not exceeding a division of 8,000 or 10,000 men, and even then it is only to be resorted to as an unavoidable evil."
3. —By regular requisitions
"In all assemblages of troops in their own country there is no difficulty in subsisting by regular requisitions; neither, as a rule, is there any in retrograde movements. On the other hand, in all movements into a country of which we are not in possession, there is very little time for such arrangements, seldom more than the one day which the advanced guard is in the habit of preceding the army. With the advanced guard the requisitions are sent to the local officials, specifying how many rations they are to have ready at such and such places. As these can only be furnished from the immediate neighbourhood, that is, within a circuit of a couple of miles round each point, the collections so made in haste will never be nearly sufficient for an army of considerable strength, and consequently, if the troops do not carry with them enough for several days, they will run short. It is therefore the duty of the commissariat to economise what is received, and only to issue to those troops who have nothing. With each succeeding day, however, the embarrassment diminishes; that is to say, if the distances from which provisions can be procured increase in proportion to the number of days, then the superficial area over which the contributions can be levied increases as the squares of the distances gained. If on the first day only four square miles have been drawn upon, on the next day we shall have sixteen, on the third, thirty-six; therefore on the second day twelve more than on the first, and on the third day twenty more than on the second."
"But now, if a war is not so decisive in its results, if its operations are not so comprehensive as is consistent with its real nature, then the requisition system will begin to exhaust the country in which it is carried on to that degree that either peace must be made, or means must be found to lighten the burden on the country, and to become independent of it for the supplies of the army. The latter was the case of the French army under Buonaparte in Spain, but the first happens much more frequently."
""Not only were stores of provisions collected, either by purchase or by deliveries in kind from the landed estates (Dominiallieferungen), consequently from distant points, and lodged in magazines, but they were also forwarded from these by means of special wagons, baked near the quarters of the troops in ovens temporarily established, and from thence again carried away at last by the troops, by means of another system of transport attached to the army itself. We take a glance at this system not merely from its being characteristic of the military arrangements of the period, but also because it is a system which can never be entirely done away; some parts of it must continually reappear."
Supply of fodder for horses
"The feeding of horses by an artificial system of supply is, however, an experiment which has not been tried, because forage is much more difficult to provide on account of its bulk. A ration for a horse weighs about ten times as much as one for a man, and the number of horses with an army is more than one-tenth the number of men, at present it is one-fourth to one-third, and formerly it was one-third to one-half, therefore the weight of the forage required is three, four, or five times as much as that of the soldier's rations required for the same period of time; on this account the shortest and most direct means were taken to meet the wants of an army in this respect, that is by foraging expeditions. Now these expeditions occasioned great inconvenience in the conduct of war in other ways, first by making it a principal object to keep the war in the enemy's country; and next because they made it impossible to remain very long in one part of the country."
"Forage, of which, as we have before said, there is usually at first the least deficiency, will run short soonest if a country begins to become exhausted, for it is the most difficult supply to procure from a distance, on account of its bulk, and the horse feels the effect of low feeding much sooner than the man. For this reason, an over-numerous cavalry and artillery may become a real burden, and an element of weakness to an army."
Clausewitz served with the Russian Army for the 1812-14 campaigns only rejoining the Prussian Army in time for the 1815 campaign. During his time in the Russian Army, the supply service did not always run smoothly and there were numerous instances of failures by the commissariat. Further reading can be found in the section "Supply System and Administration of the Army" of this Russian Army website.
"Since the doing away with tents and the introduction of the system of subsisting troops by compulsory demands for provisions on the spot, the baggage of an army has been very sensibly diminished, and as a natural and most important consequence we look first for an acceleration in the movements of an army, and, therefore, of course, an increase in the length of the day's march. This, however, is only realised under certain circumstances.
Marches within the theatre of war have been very little accelerated by this means, for it is well known that for many years whenever the object required marches of unusual length it has always been the practice to leave the baggage behind or send it on beforehand, and, generally, to keep it separate from the troops during the continuance of such movements, and it had in general no influence on the movement, because as soon as it was out of the way, and ceased to be a direct impediment, no further trouble was taken about it, whatever damage it might suffer in that way. Marches, therefore, took place in the Seven Years' War, which even now cannot be surpassed; as an instance we cite Lascy's march in 1760, when he had to support the diversion of the Russians on Berlin, on that occasion he got over the road from Schweidnitz to Berlin through Lusatia, a distance of forty-five miles, in ten days, averaging, therefore, 4½ miles a day, which, for a corps of 15,000, would be an extraordinary march even in these days.
On the other hand, through the new method of supplying troops the movements of armies have acquired a new retarding principle. If troops have partly to procure supplies for themselves, which often happens, then they require more time for the service of supply than would be necessary merely to receive rations from provision wagons. Besides this, on marches of considerable duration troops cannot be encamped in such large numbers at any one point; the divisions must be separated from one another, in order the more easily to manage for them. Lastly, it almost always happens that it is necessary to place part of the army, particularly the cavalry, in quarters. All this occasions on the whole a sensible delay. We find, therefore, that Buonaparte in pursuit of the Prussians in 1806, with a view to cut off their retreat, and Blucher in 1815, in pursuit of the French, with a like object, only accomplished thirty miles in ten days, a rate which Frederick the Great was able to attain in his marches from Saxony to Silesia and back, notwithstanding all the train that he had to carry with him.
At the same time the mobility and handiness, if we may use such an expression, of the parts of an army, both great and small, on the theatre of war have very perceptibly gained by the diminution of baggage. Partly, inasmuch as while the number of cavalry and guns is the same, there are fewer horses, and therefore, there is less forage required; partly, inasmuch as we are no longer so much tied to any one position, because we have not to be for ever looking after a long train of baggage dragging after us.
Marches such as that, which, after raising the siege of Olmutz, 1758, Frederick the Great made with 4,000 carriages, the escort of which employed half his army broken up into single battalions and companies, could not be effected now in presence of even the most timid adversary.
On long marches, as from the Tagus to the Niemen, that lightening of the army is more sensibly felt, for although the usual measure of the day's march remains the same on account of the carriages still remaining, yet, in cases of great urgency, we can exceed that usual measure at a less sacrifice.
Generally the diminution of baggage tends more to a saving of power than to the acceleration of movement."
Interestingly, Clausewitz claims that although armies both lightened their baggage load, reduced the number of horses as a result and switched from magazine supply to local foraging, there was not much increase in speed or distance marched in a day between the Seven Years War and the Befrieungskrieg of 1813. The result was a more consistent marching pattern and freedom to operate. However it should be remembered that Frederick the Great had by far the most mobile of the armies of the Seven Years War and his march from Saxony to Silesia was supplied by depots along his route largely through Prussian territory, not an adavnce into enemy territory. His other generals, Prince Ferdinand of Brunswick and Prince Henry were more constrained in their operations and the French armies and the 'Reichsarmee' were slower still.
"In former times, that is, before armies grew once more to considerable dimensions, before wars became of greater duration, and their partial acts brought into connection with a whole or general plan, and up to the time of the war of the French Revolution, armies always used tents. This was their normal state. With the commencement of the mild season of the year they left their quarters, and did not again take them up until winter set in. Winter quarters at that time must to a certain extent be looked upon as a state of no war, for in them the forces were neutralised, the whole clockwork stopped, quarters to refresh an army which preceded the real winter quarters, and other temporary cantonments, for a short time within contracted limits were transitional and exceptional conditions.
This is not the place to enquire how such a periodical voluntary neutralisation of power consisted with, or is now consistent with the object and being of war; we shall come to that subject hereafter. Enough that it was so.
Since the wars of the French Revolution, armies have completely done away with the tents on account of the encumbrance they cause. Partly it is found better for an army of 100,000 men to have, in place of 6,000 tent horses, 5,000 additional cavalry, or a couple of hundred extra guns, partly it has been found that in great and rapid operations a load of tents is a hindrance, and of little use.
But this change is attended with two drawbacks, viz., an increase of casualties in the force, and greater wasting of the country.
However slight the protection afforded by a roof of common tent cloth,—it cannot be denied that on a long continuance it is great relief to the troops. For a single day the difference is small, because a tent is little protection against wind and cold, and does not completely exclude wet; but this small difference, if repeated two or three hundred times in a year, becomes important. A greater loss through sickness is just a natural result.
How the devastation of the country is increased through the want of tents for the troops requires no explanation.
One would suppose that on account of these two reactionary influences the doing away with tents must have diminished again the energy of war in another way, that troops must remain longer in quarters, and from want of the requisites for encampment must forego many positions which would have been possible had tents been forthcoming."
One of the changes associated with this is the introduction of the greatcoat, which appeared in 1803 in the British Army, so that the soldier no longer had to rely just on his dress coat and waistcoat and seek shelter in a tent. Sentries had often shared a cloak but greatcoats were issued to every man and became common across Europe around this time.