to Davout and Murat what part they were to play in his plans. Murat would command the huge body of cavalry, a great battering ram of four divisions, with a nominal strength of 40,000, which was to spearhead the attack. Napoleon wanted to fight and defeat the Russians as quickly as possible, so he decided to strike them at the point where they might feel strong enough to make a stand, which meant a frontal attack at Vilna. He would attack Barclay’s First Army, using Davout’s 1st Corps of 70,000 men, flanked by Ney’s 3rd Corps of 40,000 to the north and backed up by the Guard, numbering some 40,000. Prince Eugène’s 4th and St Cyr’s 6th Corps, totalling 67,000 Italians, Bavarians and Croats as well as Frenchmen, would advance to the south of this thrust, driving a wedge between Barclay and Bagration. Further south, Jérôme was to advance against Bagration with three other army corps (5th Polish, 7th Saxon and 8th Westphalian), altogether some 60,000 men. In the north, Marshal Macdonald’s 10th Corps, made up of Prussians as well as Frenchmen, would cross the Niemen at Tilsit and advance on Riga, while Oudinot’s 2nd Corps supported both him and the main strike force by attacking Barclay’s right wing. South of the Pripet, Schwarzenberg’s Austrians were to mark Tormasov’s Third Army.
It is impossible to be precise about the numbers involved. On paper, the overall strength of the forces poised for invasion was 590,687 men and 157,878 horses, while the total number of French and allied troops in the whole theatre of operations, including Poland and Germany, was 678,000. But these figures beg many questions.26
The strength of an army which has taken up positions, as the Russian had done over the months, can be established fairly accurately, as the units are concentrated in one place, and there is little reason or scope for anyone to absent themselves for more than the few hours it might take to report to headquarters or pick up some stores. But an army on the move is far more volatile.
Whatever the technical strength of any unit on campaign, it is never concentrated in a single place, or even area, at one time. It always leaves a skeleton force, sometimes a whole battalion, at its depot. It does not move, lock stock and barrel, from one place to another: its head races ahead, leaving its body and tail to catch up, which they occasionally do, only to be left behind once more, in the manner of a huge centipede. It is constantly leaving behind platoons or smaller clusters of men to hold, defend or police areas. Numbers vary, almost always downwards, with every day.
A company of 140 men marches out from town A on its way to town B. On the morning they are setting off, it turns out that three of the men are too ill to march, so they are left behind, in the care of a corporal and two orderlies. In addition, one of the captain’s four horses is lame, and a second is out of condition, so they remain behind, in the care of an orderly. One of the company’s ammunition caissons or luggage wagons has a broken axle, and remains in town A while it is being repaired, in the care of two men. One man failed to report for roll call before the company marched out. This means that only 130 men actually set off. Along the way, eight men are detailed to find supplies, and they set off into the countryside with a couple of wagons. Another ten men fall behind in the course of the day’s twenty-five-kilometre trek, and, another of the wagons having broken a wheel, two more are detailed to look after it until it can be fixed. By that evening, the company with a technical strength of 140 men can only assemble 110 men in a single place. And that diminution took place without the intervention of disease, bad weather or the enemy. It would probably have been more drastic in the case of a cavalry squadron, where lameness and saddle sores played their part. And there has been no account taken of desertion, which is far easier on the march than in a fixed position, and which increases the further an army is from its home ground.* Some of the men left behind catch up, but the faster and further an army moves, the fewer do, and so the gap between those catching up and those falling away widens. If that same company had to make a forced march over three days and then fight on the fourth, its captain would be lucky to lead much more than half its paper strength into battle – less than a week after setting out.
Numbers arrived at by means of adding up the paper strength of the units present in an army can therefore serve only as a rough guide to the situation on the ground. It is generally accepted that the strength of the Grande Armée as it invaded Russia was about 450,000, but this has been arrived at by computing theoretical data, and the reality was certainly very different.
On 14 June Napoleon issued a circular to the commanders of every corps insisting that they must provide honest figures on the numbers of the able-bodied, the sick and deserters, as well as the dead and the wounded. ‘It has to be made clear to the individual corps that they must regard it as a duty towards the Emperor to provide him with the simple truth,’ ran the order.27
This admonition was ignored. ‘He was led astray in the most outrageous way,’ wrote General Berthézène of the Young Guard. ‘From the marshal to the captain, it was as if everyone had come together to hide the truth from him, and, although it was tacit, this conspiracy really did exist; for it was bound together by self-interest.’ Napoleon was always angry when provided with dwindling figures, particularly if these could not be explained by battle casualties, so those responsible simply hid the losses from him. Berthézène went on to say that the Guard, which was usually written up as being nearly 50,000 strong, never exceeded 25,000 during the whole campaign; that the Bavarian contingent, given as 24,000, was never stronger than 11,000; and that the whole Grande Armée was no larger than 235,000 when it crossed the Niemen. One can quibble with his estimates, but not with his argument, which is supported by others.28
Russian estimates of the French forces at this stage were much lower than the generally accepted figures (and intriguingly close to Berthézène’s), which has surprised historians and led them to believe that they must have had very poor intelligence. But it may simply be that while French figures were based on paper computations, the Russians based their estimates on reports from spies, and those reports may have been more accurate as to the numbers of troops actually present than the paper calculations.
It would be rash to try to be precise, but a sensible guess would be that no more than three-quarters and possibly as little as two-thirds of the 450,000 crossed the Niemen in the first wave, and that the remainder, if and when they caught up with the main body, were only plugging gaps left by men dropping away. At the same time, it would be difficult to overestimate the number of civilians following in the wake of the army, and a figure of 50,000 would certainly be on the conservative side.
Having fixed his plan, Napoleon applied himself to putting it into action. Speed was of the essence. He wanted to get at the Russian army before it had time to withdraw or concentrate. Speed was also essential for logistical reasons: with the shortage of supplies available, the ground was burning the feet of the Grande Armée. He was counting on being able to confront and defeat the Russian army inside three weeks, as he could not possibly take with him supplies for any longer.
From Danzig, he raced on to Marienburg, Elbing and Königsberg. At every point along his frantic journey he inspected troops, artillery parks and supply depots. During the four days he spent at Königsberg he inspected the stores and boatyards as, having seen for himself the state of the local roads and appreciated the shortage of draught animals, he had decided to despatch as many supplies as possible up the Niemen and its tributary the Vilia to reach him once he had occupied Vilna.
As there would be scant possibility of finding provisions along the way, he had given orders that every soldier should carry with him four days’ ration of bread and biscuit in his knapsack, and every regiment a twenty-day ration of flour in its wagons. But his orders could only ever be as productive of results as the land was fertile in the necessary means, and they were meaningless where there was nothing to be had.
On 22 June General Deroy, a splendid warrior in his eighties who had more than sixty years’ military service behind him and would soon die in battle commanding one of the Bavarian divisions, reported to his monarch that he did not see how they were going to survive at all. ‘I