Mr Laurens sailed for Holland in August, 1780, but was captured a few days afterwards by a British frigate, which conveyed him to Newfoundland, whence he was sent to England and imprisoned in the Tower. When this intelligence reached Congress, it was resolved to transfer his appointment to another person, and on the 29th of December Mr Adams was commissioned to negotiate a treaty of amity and commerce with the United Provinces, and he was furnished with separate letters of credence as Minister Plenipotentiary to the States-General and to the Prince of Orange. The state of parties in Holland, and particularly the influence of England there, rendered unavailing all advances of the American Minister towards a treaty.
It having been intimated to Mr Adams, by the Duc de la Vauguyon, French Ambassador in Holland, that a treaty of peace was in prospect through the mediation of Russia and Austria, and that Count de Vergennes would be glad to see him on the subject at Versailles, he set off for Paris on the 6th of July, 1781. He had several interviews with the Count de Vergennes, and a correspondence of some length. After remaining three weeks at Paris and Versailles, without perceiving any apparent indications, that this project for a negotiation would come to maturity, he returned again to Holland.
On the 14th of June Congress appointed four other Commissioners, in conjunction with Mr Adams, to negotiate a treaty of peace, namely, Benjamin Franklin, John Jay, Henry Laurens, and Thomas Jefferson, and the first commission of Mr Adams for this purpose was annulled.
A misunderstanding having grown up between England and the United Provinces, chiefly on account of the part taken by the latter in joining the northern powers to carry into operation the plan of the armed neutrality, the French Court thought it a good opportunity for the United States to seek a treaty of alliance with Holland. This step was accordingly recommended to Congress through the French Minister at Philadelphia, and, in consequence of this suggestion, new powers were conferred on Mr Adams, dated August the 16th, by which he was commissioned to negotiate a treaty of alliance with Holland, limited in duration to the continuance of the war with England, and conformable to the treaties then subsisting with France.
The political relations between the several Provinces of Holland were such, however, that the process of negotiation went on heavily and slowly. The English interest still continued strong, even after the war had begun, and embarrassments of various kinds were thrown in the way, which required no common share of sagacity, firmness, and perseverance to overcome. All these at length yielded, and on the 8th of October, 1782, a treaty of commerce between the United States and Holland, and a convention concerning recaptures, were signed at the Hague.
Dr Franklin and Mr Jay had now been for three or four months actively engaged in the negotiation of peace at Paris. Having thus brought affairs to a happy issue in Holland, Mr Adams hastened to join the Commissioners, and arrived in Paris before the end of October. From that time till the Preliminary Articles were signed, November the 30th, he applied himself unremittingly with his colleagues to the details of the negotiation. He also took part in the discussions respecting the Definitive Treaty, which followed from time to time, and was one of the signers of that instrument.
In the winter of 1784 he was in Holland. In January, 1785, he was appointed the first American Minister Plenipotentiary to the Court of St James's. While in England, he wrote his Defence of the American Constitutions. In the year 1788 permission was granted him to return home, where he arrived after an absence of almost nine years, during the whole of which period he had been employed in services of the highest responsibility and importance. He was shortly afterwards elected Vice President of the United States, under the first Presidency of Washington.