The Duke of Weymar began the campaign of 1638 in a very brilliant manner[326]: he gained a signal victory over the Imperialists on the 2d of March; and, what was very remarkable, all the enemy's generals were taken in this engagement, and among the rest the famous John de Vert, whose name was become the terror of the Parisians. The King, on receiving this important news, immediately sent notice of it to Grotius; signifying that he knew no body would receive it with more pleasure. March 16[327], he had an audience of the King, at which he thanked his Majesty for sending him the first news of the victory gained in Germany, and doing him the justice to believe that it would give him infinite satisfaction: he added, that it was a happy prognostic for the rest of the campaign: that God had confounded the pride of the Imperialists, who publicly gave out that they intended to come to pillage Paris[328]. He said he had certain advice by letters from the army, that the enemy's generals had been at great pains to provide themselves with maps of France, in order to examine at what part they could best enter it. He pressed the King to put the Duke of Weymar in a condition, by sending him immediately a considerable reinforcement, to make a proper advantage of this happy beginning of the campaign; and concluded his compliment with good wishes for the King's happiness and that of his posterity, of which there began to be then some hope. People flattered themselves the Queen was with child; and she was actually in the third month of her pregnancy. The King received this compliment with great gaiety: he promised to send immediately five or at least three thousand foot to the Duke of Weymar, with some horse, under the command of the Count de Guebriant. Grotius had a fresh audience of the King on the 19th of April, 1638[329]. He represented to his Majesty, that though the Duke of Weymar had begun the year well, he could not make great progress if an additional force were not sent him: that by proceeding so slowly in this measure, the enemy had got time to recruit their army: and if it were not now taken with great expedition, they would lose the fruits of their late advantages, and the affairs of the allies suffer much; that her Swedish Majesty was in the same disposition with the King, and had no other view than to procure an equitable, honourable, and lasting peace; that the only way to obtain this great end was by making the most powerful efforts: that the Queen, agreeable to his Majesty's desire, would accept of the mediation of the Venetians, provided the republic would treat her with due respect: that his most Christian Majesty being of opinion that a long truce would lead to a peace, the Queen, who was sensible of his great prudence, had given her Ambassador in France full power to treat of this affair, and to draw up a plan of it in conjunction with such persons as the King should nominate. After this speech Grotius delivered to Lewis XIII.