Lisbon, 23 Sep 1791. Despite Thomas Barclay’s arrival in Oporto, he still has not received the letters Barclay brought from America for him.—Two British packets and a cutter from England with dispatches for Mr. Walpole have arrived since his letter of the 10th instant. Peace has been concluded between the Emperor and the Porte, and peace will soon follow between the Empress and the Porte, “unless the latter shall consent to be abandoned by the Mediating Powers, whose Ministers have agreed upon the terms with the former. The Empress will then have terminated the war in as favorable a manner as she could have desired. “—The recent interview between the Emperor, the King of Prussia and the Elector of Saxony is supposed to have concerned Poland and given offense to Russia. Letters delivered to the Margrave of Anspach by the last packet indicate that Russia, Austria, and Prussia have agreed that no branch of their royal families should marry the heiress of the Polish throne. He learned last night from the Swedish agent that the King of Sweden was going to St. Petersburg.—There are many different rumors about Louis xvi’s acceptance of the French constitution and the attitude of the other European powers toward France. The Duke of Alafoñes told him on Sunday that the Queen had heard nothing from France about the constitution. The Prussian minister informed him the night before last that the king had approved the constitution. But yesterday he could not ascertain from the Papal nuncio or the Spanish chargé d’affaires the basis for the report of the king’s acceptance, and today none of the Gazettes just received from France contain anything bearing on this question.—The Portuguese minister to the United States, [Cypriano Ribeiro] Freire, is about to leave London for America.—The Spanish government has announced a new prohibition “concerning French publications and manuscripts.”—P.S. Barclay has arrived in the Tagus, but the letters he brought with him have still not been received.