The Prussian-American Treaty of Amity and Commerce was concluded on 10 September 1785. But negotiations began on 10 November 1784 when the American commissioners submitted a draft treaty to the Baron von Thulemeier, Prussian minister at The Hague, and were, for all intents and purposes, completed on 14 March 1785 when the commissioners sent their response to Prussian proposals for alterations in the commissioners’ text.

The proposed treaty with Prussia was the commissioners’ first exercise of their plenipotentiary powers to negotiate and sign treaties with European nations. On 8 October 1784 Thulemeier wrote to the commissioners to acknowledge their letter of 9 September notifying him of their new commission (both above). Thulemeier indicated Prussia’s willingness to negotiate a treaty and noted that he had received full powers to conclude an agreement. Thulemeier assumed in his letter that negotiations would resume on the draft treaty that he had sent to John Adams on 9 April (above). Those negotiations were broken off owing to the commissioners’ need to submit the draft to Congress because they lacked the power to negotiate and sign a treaty. But such was not to be the case.

Instead the commissioners wrote to Thulemeier on 10 November and enclosed a new draft, based not on the earlier Prussian proposal but on a model treaty drafted by Thomas Jefferson (Nos. I and II, below). In substance the new draft differed only slightly from Thulemeier’s of April, but there were alterations. The most notable were the omission of the earlier draft’s Articles 3 and 4, which dealt specifically with Prussian concerns, and the inclusion of Articles 13 and 23, which were wholly new. Moreover, the April draft was founded on the 1783 Swedish-American treaty, but Jefferson’s model, intended originally for a never-to-be-concluded Danish-American treaty, was based on a variety of sources. These included drafts of a Danish-American treaty exchanged by Benjamin Franklin and Ernst Frederik von Walterstorff in 1783; the commercial treaties concluded in 1778, 1782, and 1783 with France, the Netherlands, and Sweden; a 1783 draft of a never-completed commercial treaty with Portugal; and the commissioners’ instructions of 7 May 1784. For a detailed examination of Jefferson’s composition of and his sources for the model treaty, see Jefferson, Papers , 7:463–490.

The Prussian diplomat received the new draft on 26 November, made a French translation, and by 10 December had sent it off to the foreign ministry in Berlin (No. IV, below). Had the negotiations over Thulemeier’s April draft been renewed, the treaty would likely have been concluded very quickly since the Americans had proposed few changes to that document. But complications were introduced when an entirely new document was offered for consideration, which Thulemeier attributed to the commissioners’ new instructions and the Prussians viewed as a “contre-project.” This was particularly so regarding the omission of Articles 3 and 4 of the earlier draft, but there was also an apparent conflict between the American and Prussian views of commercial relations. This was evident from Thulemeier’s letter to the commissioners of 24 January 1785, with which he enclosed his French translation of the treaty with the Prussian foreign ministry’s suggestions for changes in the treaty provisions (No. VI, below). In a letter of the same date to Adams, Thulemeier indicated the necessity of the Americans’ agreeing to the principal Prussian reservations if a treaty was to be concluded, confidential advice that Adams relayed to his colleagues (Nos. V and VII, below). Even allowing for the resolution of the 375 Prussian-American differences and the fact that the commissioners were in France and Thulemeier was in the Netherlands, the negotiations proceeded expeditiously. On 14 March the commissioners sent off their response to the Prussian proposals (No. VIII, below) and on 3 May, after consulting with his superiors, Thulemeier informed the commissioners that the two sides were in agreement over the treaty’s final form and it only remained for the Americans to transcribe an English version of the agreed upon text so that he could prepare a French translation for final review in Berlin. Franklin and Jefferson—Adams by then had gone to London—did so on 26 May, and after arrangements were made for the treaty’s signature at Paris, Passy, London, and The Hague, the agreement was finally concluded on 10 September when Thulemeier signed at The Hague (Jefferson, Papers , 8:134–135, 165–166; Miller, Treaties , 2:162–184).

Some explanation is required regarding the documents as printed below and the nature of their annotation. The English text of the draft treaty is derived from the copy made by David Humphreys and included in the Letterbook that he kept for the commissioners. The French translation accompanying it was enclosed by Thulemeier in his letter of 24 January. There it was placed side by side with the Prussian “Observations,” the treaty in the left column, the “Observations” in the right column. The editors decided that in presenting the treaty material the need for clarity required that the English and French texts be printed together and that the Prussian “Observations” should appear with Thulemeier’s letter of 24 January, with which they were enclosed. In annotating the treaty the editors have indicated where significant changes were made, resulting either from the Prussian proposals or from the commissioners’ response. However, for the justification or explanation of the alterations that either did or did not take place, see the Prussian and American commentaries on the treaty, Nos. VI and VIII, below.