On July 31, 1870, Bismarck left Berlin with the King for the seat of war, for, as in 1866, he was to accompany the army in the field. For the next few months indeed Germany was to be governed from the soil of France, and it was necessary for the Minister to be constantly with the King. Bismarck never forgot that he was a soldier; he was more proud of his general's uniform than of his civil rank, and, though not a combatant, it was his pride and pleasure that he should share something of the hardships and dangers of war. He was as a matter of fact never so well as during the campaign: the early hours, the moderate and at times meagre food, the long hours in the saddle and the open air, restored the nerves and health which had been injured by the annoyances of office, late hours, and prolonged sedentary work. He was accompanied by part of the staff of the Foreign Office, and many of the distinguished strangers who followed the army were often guests at his table; he especially shewed his old friendliness for Americans: General Sheridan and many others of his countrymen found a hearty welcome from the Chancellor.

It was not till the 17th of August that the headquarters came up with the fighting front of the army; but the next day, during the decisive battle of Gravelotte, Bismarck watched the combat by the side of the King, and, as at Königgrätz, they more than once came under fire. At one period, Bismarck was in considerable danger of being taken prisoner. His two sons were serving in the army; they were dragoons in the Cuirassiers of the Guards, serving in the ranks in the same regiment whose uniform their father was entitled to wear. They both took part in the terrible cavalry charge at Mars-la-Tour, in which their regiment suffered so severely; the eldest, Count Herbert, was wounded and had to be invalided home. Bismarck could justly boast that there was no nepotism in the Prussian Government when his two sons were serving as privates. It was not till the war had gone on some weeks and they had taken part in many engagements, that they received their commissions. This would have happened in no other country or army. This was the true equality, so different from the exaggerated democracy of France,—an equality not of privilege but of obligation; every Pomeranian peasant who sent his son to fight and die in France knew that the sons of the most powerful man in the country and in Europe were fighting with them not as officers but as comrades. Bismarck was more fortunate than his friends in that neither of his sons—nor any of his near relatives—lost his life; Roon's second son fell at Sedan, and the bloody days of Mars-la-Tour and Gravelotte placed in mourning nearly every noble family in Prussia.

From Gravelotte to Sedan he accompanied the army, and he was by the King's side on that fatal day when the white flag was hoisted on the citadel of Sedan, and the French general came out of the town with the message that Napoleon, having in vain sought death at the head of his troops, placed his sword in the hands of the King of Prussia.

The surrender of Sedan was a military event, and the conditions had to be arranged between Moltke and Wimpffen, who had succeeded MacMahon in command, but Bismarck was present at the conference, which was held in his quarters, in case political questions arose. As they rode down together to Doncheroy he and Moltke had agreed that no terms could be offered except the unconditional surrender of the whole army, the officers alone being allowed to retain their swords. Against these conditions Wimpffen and his companions struggled long, but in vain. Moltke coldly assured them that they could not escape, and that it would be madness to begin the fight again; they were surrounded; if the surrender were not complete by four o'clock the next morning the bombardment of the town would begin. Wimpffen suggested that it would be more politic of the Germans to show generosity; they would thereby earn the gratitude of France, and this might be made the beginning of a lasting peace; otherwise what had they to look forward to but a long series of wars? Now was the time for Bismarck to interfere; it was impossible, he declared, to reckon on the gratitude of nations; at times men might indeed build with confidence on that of a sovereign and his family; "but I repeat, nothing can be expected from the gratitude of a nation." Above all was this true of France. "The Governments there have so little power, the changes are so quick and so unforeseen, that there is nothing on which one can rely." Besides, it would be absurd to imagine that France would ever forgive us our successes. "You are an irritable and jealous people, envious and jealous to the last degree. You have not forgiven us Sadowa, and would you forgive us Sedan? Never."

They could not therefore modify the terms in order to win the gratitude and friendship of France; they might have done so had there been prospects of immediate peace. One of the officers, General Castelnau, announced that he had a special message from Napoleon, who had sent his sword to the King and surrendered in the hope that the King would appreciate the sacrifice and grant a more honourable capitulation. "Whose sword is it that the Emperor Napoleon has surrendered?" asked Bismarck; "is it the sword of France or his own? If it is the sword of France the conditions can be greatly softened; your message would have an extraordinary importance." He thought and he hoped that the Emperor wished to sue for peace, but it was not so. "It is only the sword of the Emperor," answered the General. "All then remains as it was," said Moltke; he insisted on his demands; Wimpffen asked at least that time might be allowed him to return to Sedan and consult his colleagues. He had only come from Algeria two days before; he could not begin his command by signing so terrible a surrender. Even this Moltke refused. Then Wimpffen declared the conference ended; rather than this they would continue the battle; he asked that his horses might be brought. A terrible silence fell on the room; Moltke, with Bismarck by his side, stood cold and impenetrable, facing the three French officers; their faces were lighted by two candles on the table; behind stood the stalwart forms of the German officers of the staff, and from the walls of the room looked down the picture of Napoleon I. Then again Bismarck interfered; he begged Wimpffen not in a moment of pique to take a step which must have such horrible consequences; he whispered a few words to Moltke, and procured from him a concession; hostilities should not be renewed till nine o'clock the next morning. Wimpffen might return to Sedan and report to the Emperor and his colleagues.

It was past midnight when the conference broke up; before daybreak Bismarck was aroused by a messenger who announced that the Emperor had left Sedan and wished to see him. He hastily sprang up, and as he was, unwashed, without breakfast, in his undress uniform, his old cap, and his high boots, shewing all the marks of his long day in the saddle, he mounted his horse and rode down to the spot near the highroad where the Emperor in his carriage, accompanied by three officers and attended by three more on horseback, awaited him. Bismarck rode quickly up to him, dismounted, and as he approached saluted and removed his cap, though this was contrary to etiquette, but it was not a time when he wished even to appear to be wanting in courtesy. Napoleon had come to plead for the army; he wished to see the King, for he hoped that in a personal interview he might extract from him more favourable terms. Bismarck was determined just for this reason that the sovereigns should not meet until the capitulation was signed; he answered, therefore, that it was impossible, as the King was ten miles away. He then accompanied the Emperor to a neighbouring cottage; there in a small room, ten feet square, containing a wooden table and two rush chairs, they sat for some time talking; afterwards they came down and sat smoking in front of the cottage.

"A wonderful contrast to our last meeting in the Tuileries," wrote Bismarck to his wife. "Our conversation was difficult, if I was to avoid matters which would be painful to the man who had been struck down by the mighty hand of God. He first lamented this unhappy war, which he said he had not desired; he had been forced into it by the pressure of public opinion. I answered that with us also no one, least of all the King, had wished for the war. We had looked on the Spanish affair as Spanish and not as German."

The Emperor asked for more favourable terms of surrender, but Bismarck refused to discuss this with him; it was a military question which must be settled between Moltke and Wimpffen. On the other hand, when Bismarck enquired if he were inclined for negotiations for peace, Napoleon answered that he could not discuss this; he was a prisoner of war and could not treat; he referred Bismarck to the Government in Paris.

This meeting had therefore no effect on the situation. Bismarck suggested that the Emperor should go to the neighbouring Château of Belle Vue, which was not occupied by wounded; there he would be able to rest. Thither Bismarck, now in full uniform (for he had hurried back to his own quarters), accompanied him, and in the same house the negotiations of the previous evening were continued; Bismarck did not wish to be present at them, for, as he said, the military men could be harsher; and so gave orders that after a few minutes he should be summoned out of the room by a message that the King wished to see him. After the capitulation was signed, he rode up with Moltke to present it to the King, who received it on the heights whence he had watched the battle, surrounded by the headquarters staff and all the princes who were making the campaign. Then, followed by a brilliant cavalcade, he rode down to visit the captive sovereign.

Bismarck would at this time willingly have made peace, but there was no opportunity of opening negotiations and it is doubtful whether even his influence would have been able successfully to combat the desire of the army to march on Paris. On September 4th, the march, which had been interrupted ten days before, was begun.