Fighting in a mine, a tunnel or a ditch used to undermine a castle wall or break into a fortification, was in the late Middle Ages an effective but dangerous tactic, and such combats had a special prestige in a warrior culture where "doing more" than somebody else counted for a lot.
There is a passage in the Chronicle of the Good Duke in which fighting in a mine allows a number of different people to increase their renown and honor, most notably the good Duke and his fighting retinue. At the siege of Vertreuil in 1385, the good Duke decided that the English-held position could only be taken by mining. When the mine was ready to take an attacking force, the English did their best to stop the attack by sallying out through the gates to take on the Frenchmen above ground before the mine could be used. The attack was unsuccessful but it did cause unexpected casualties. The Duke acted almost immediately to get things moving in the right direction.
Châteaumorand remembered it this way:
The same day the Duke of Bourbon took a dozen knights and some squires with him, saying: "I wish to go see the mine;" which he would not have done if he had no hope of combat there; so the Duke went putting himself right up front, and sent Le Borgne de Veaulce before him and said to him, "Borgne, go ahead since you know the people of this castle, and ask them inside if there's a knight coming forward, and tell them that he will find who will receive him to fight in the mine." Then Le Borgne de Veaulce called to ask if they had no knight who wished to perform arms. So they told him no, but with them was a high gentleman who had a good company inside, and was Lieutenant of the captain and was all ready and prepared to perform arms with whomever wished to come. And Le Borgne de Veaulce answered "Come forward and see one here who is ready," not wishing to name his master. And then the Duke of Bourbon advanced in the mine, and from the other side likewise came the squire which those of the castle had mentioned, who was called Reynaud de Montferrand…
When the fight began, some of the Duke's men shouted out his battle cry and Reynaud heard them, disengaged, and asked with astonishment if this was actually the Duke of Bourbon. On being told yes, Reynaud seems to have been taken by the unusual situation he found himself in, and dared to ask the Duke for a favor.
"…Tell him that I request that it please him that in this honorable place [the mine, where only the most courageous would risk themselves] where he is that he should make me a knight by his hand, for I will never have it more honorably. And for his honor and valiance I am ready to surrender the place to him."
After the briefest of negotiations, the Duke "who observed that all these things were to his great honor," accepted the surrender, if the keys to the fortification were turned over immediately. This was done and Reynaud de Montferrand was knighted on the spot. To increase the honorable nature of this special moment, however, the Duke added on another condition:
…he ordered that Montferrand would surrender the place the next day. And further it was ordered that the knights and squires who were there with the Duke of Bourbon should bear arms the next day inside their mine with those of the castle one side against the other, which M. John l'Aye the marshal would oversee, so that each would be satisfied to have fought in the mine… [And in fact the next day, this combat took place.] …They were not able to fight except with swords, because the opening had a width of only a foot and a half; but each one did his duty well, one after the other, according to the place, which was narrow and because the night grew dark, the companions returned to the tents. And the next day the Duke of Bourbon sent one of his marshals [to receive the promised surrender, which took place as agreed. Then] Reynaud de Montferrand knelt before the Duke and said to him, "My very redoubtable lord, I thank you most humbly for the benefits and honors which have come to me from you, to be a knight by the hand of so high and valiant a Prince as you are; so it is an honor to me and all my lineage forever." The Duke answered, "M. Reynaud, chivalry is very strong in you, for you are a valiant man of good lineage."
What does this story tell us about the Duke? He did very well by his practical goals and his reputation by taking unusual risks with himself, by entering the mine and daring the garrison, especially its leaders, to resist him. He won big with this tactic; his reputation was already so great, mainly perhaps because of his rank, but certainly also because of his experience as a warrior prince, that he was able to take the fortification with no further harm to himself or even his enemies. And like a winner at the gambling table, his victory increased his reserves of honor rather than diminishing them.
But the Duke was not content simply to increase his own renown. The Duke went out of his way to share the glory with his most valued captains. He did so by insisting that they not be cheated of the opportunity to fight in a mine. Even if nothing was at stake now except renown, the stories that could be told afterwards would amaze listeners. Hours of strenuous and dangerous fighting took place, until the level of light fell to the point that combat could not continue. Here we see the Chronicle of the Good Duke transformed into the Chronicle of the Good Duke's men. It is one more tale of "that old gang of mine," this time, in the mine.
The group renown won on this occasion turned out to be as valuable in a practical sense as the personal renown gained by the Duke, as we see almost immediately in the description of the army's return to Poitiers, which is described in the same short chapter as the taking of Vertreuil and the fight in the mine. Châteaumorand shows how warriors who had not benefited from the patronage of the good Duke saw him and his men. Duke Louis left Vertreuil intending to go to Paris and attend the King, something he was always under obligation to do whether it was convenient for him or not. At Poitiers he found himself delayed by the leading people of that strategic and historic city. The Poitevins, meaning the local seigneurs, who were at least in theory military men themselves, were worried about three places in the region that were occupied by the enemy and whose garrisons were destroying the countryside. The Poitevins asked Duke Louis for half of his men to stay at Poitou and deal with this menace. Duke Louis responded by saying "You are 600 men-at-arms, and I have another 600 of my house which I lead; you 600 will easily take these three places." So the Poitevins said to the Duke, "We are not able to do anything without your people; give us a captain to lead this war. They will be well paid and we will fly your banner, and six or seven banners of the people of your house." The Duke relented and traded 200 of his men at arms for 200 Poitevins; the numbers of each force remained the same but the army in Poitou was now stronger. The Poitevin army was to be commanded by nine of the Duke's best knights and three squires. These included several warriors well known to modern military historians, including Reynaud de Roye, Boucicault, and Châteaumorand himself. But maybe more to the point, of the twelve Châteaumorand names as leading members of this reinforced Poitevin force were four men who had just fought in the mine at Vertreuil. Their names and banners were regarded as valuable military resources; because of their association with the good Duke and their willingness to follow his path to glory and renown they were precisely the kind of men you would want in the forefront of your army.
Image: Verteuil? rebuilt later?