With his family about him he fixed his residence at Auteuil, near Paris, where he had an interval of comparative leisure.
The chief business of the new commission was the negotiation of a treaty with Prussia, advances toward which had first been made to Adams while at the Hague negotiating the Dutch loan, but before that treaty was ready for signature Adams was appointed by congress as Minister to the court of St. James, where he arrived in May, 1785. The English government, the feelings of which were well represented by those of the king, had neither the magnanimity nor policy to treat the new American States with respect, generosity, or justice. Adams was received with civility, but no commercial arrangements could be made. His chief employment was in complaining of the non-execution of the treaty of peace, especially in relation to the non-surrender of the western posts, and in attempting to meet similar complaints urged, not without strong grounds, by the British; more particularly with regard to the obstacles thrown in the way of the collection of British debts, which were made an excuse for the detention of the western posts. Made sensible in many ways of the aggravation of British feelings toward the new republic, whose condition immediately after the peace was somewhat embarrassing, and not so flattering as it might have been to the advocates and promoters of the revolution, the situation of Adams was rather mortifying than agreeable.
Meanwhile he was obliged to pay another visit to Holland to negotiate a new loan as a means of paying the interest on the Dutch debt. He was also engaged in a correspondence with his fellow-commissioner, Mr. Jefferson, then at Paris, on the subject of the Barbary powers and the return of the Americans held captive by them. But his most engrossing occupation at this time was the preparation of his "Defence of the American Constitution," the object of which was the justification of balanced governments and a division of powers, especially the legislative, against the idea of a single assembly and a pure democracy, which had begun to find many advocates, especially on the continent. The greater part, however, of this book--the most voluminous of his publications--consists of summaries of the histories of the Italian republics, which, by the way, was not essential to the argument.