There had once existed, five hundred yards from the right of the Black Prince’s entrenched line, a Roman road, the traces of which can still be discovered at various parts of its course, but which, even by the time of Poitiers, had disappeared as a passable way. The only approach remaining, as I have said, was that irregular lane which formed the connection between Poitiers and Nouaillé.

Now in most terrains where feudal cavalry was concerned, the existence or non-existence of a road, and its character, would be of little moment in the immediate neighbourhood of the action: for though a feudal army depended (as all armies always must) upon roads for its strategics, it was almost independent of them in its tactics upon those open fields which were characteristic of mediæval agriculture. The mounted and armoured men deployed and charged across the stubble. Those who have read the essay upon the Terrain of Crécy, which preceded this in the present series, will appreciate that the absence of a road uniting the English and French positions in that battle was of no significance to the result.

But in the particular case of Poitiers this road, and a certain cart-track leading off it, must be carefully noted, because between them they determine all that happened; and the reason of this is that the front of the English position was covered with vines.

The French method of cultivating the vine, and the condition of that cultivation in the middle of September (in all but a quite exceptionally early year so far north as Poitou), makes of a vineyard the most complete natural obstacle conceivable against the use of cavalry, and at the same time a most formidable entanglement to the advance of infantry, and a tolerable cover for missile weapons at short range.

The vine is cultivated in France upon short stakes of varying height with varying districts, but usually in this neighbourhood somewhat over four feet above the ground; that is, covering most of a man’s figure, even as he would stand to arms with a long-bow, yet affording space above for the discharge of the weapon. These stakes are set at such distances apart as allow ordered and careful movement between them, but close enough together to break and interfere with a pressed advance: their distances being determined by the fulness of the plant before the grapes are gathered, a harvest which falls in that region somewhat later than the date of the action.

Wherever a belt of vineyard is found, cultivated after this fashion, the public ways through it are the only opportunities for advance; for land is so valuable under the grape that various allotments or properties are cultivated to their outermost limit. The vineyards (which have now disappeared, but which then stood upon the battlefield) could only be pierced by the roads I have mentioned.[7]

This line, then, already well protected by the vineyards, was further strengthened by the presence of a hedge which bounded them and ran along their eastern edge upon the flat land above the depression.

I have mentioned a cart-track, which branched off on the main lane, and which is marked upon my map with the letters “A-A.” It formed, alongside with the lane, a second approach through the English line, and it must be noticed that, like the main lane, a portion of it, where it breasted the slope, was sunk in those times below the level of the land on either side.

The first thought that will strike the modern student of such a position is that a larger force, such as the one commanded by the King of France, should have been able easily to turn the defensive upon its right.

Now, first, a feudal army rarely manœuvred. For that matter, the situation was such that if John had avoided a fight altogether, and had merely marched down the great south-western road to block Prince Edward’s retreat, the move would have had a more complete effect than winning a pitched battle. The reader has also heard how the Black Prince’s sense of his peril was such that he had been prepared to treat upon any but the most shameful terms. It is evident, therefore, that if the French fought at all it was because they wanted to fight, and that they approached the conflict in the spirit (which was that of all their time) disdainful of manœuvring and bound in honour to a frontal attack. A modern force as superior in numbers as was John’s to the Black Prince’s would have “held” the front of the defensive with one portion of its effectives, while another portion marched round that defensive’s right flank. But it is impossible to establish a comparison between developed tactics and the absolutely simple plan of feudal warfare. It is equally impossible to compare a modern force with a feudal force of that date. It had not the unity of command and the elasticity of organisation which are necessary to divided and synchronous action. It had no method of attack but to push forward successive bodies of men in the hope that the weight of the column would tell.