From the Massachusetts Centinel, issue of 20 March 1790, an article about British encroachments in the disputed border around Passamaquoddy Bay in Maine and New Brunswick.
Circumstantially related by a Correspondent
There are three rivers that empty themselves into the Bay of Passamaquady [now called Passamaquoddy], the easternmost always called by the native Indians and French St. Croix, and the middle one Schooduck. Before the commencement of the late war, Gov. BARNARD sent Mr. Mitchell, a Surveyor, and several others to explore the Bay of Passamaquady, and to examine the natives, to find out which was the true river St. Croix; they accordingly did, and reported it to be the easternmost river, and returned plans of their survey as such. At the forming of the Treaty of Peace, the Commissioners had Mitchell's maps, and in fixing the boundary between that part of Nova-Scotia now called New Brunswick, and this Commonwealth, they considered it to be the river laid down by him. - After the Peace, the subjects of the British King took possession of all the lands, between the St. Croix and Schooduck rivers, (which tract is nearly as large as the State of New-Hampshire) and now hold possession of the same, under a pretence that the Schooduck is the true river St. Croix; they also claim all the islands in the Bay of Passamaquady, although many of them lay several miles to the westward of the river that they call the boundary; and have in a number of instances exercised, by force, jurisdiction over the subjects of this Commonwealth, living on those Islands. - The British Sheriff from St. Andrews, with an armed force, took a Mr. TUTTLE (formerly a Lieutenant in the American army) from his house on Moor Island [likely Moose Island], and conveyed him to St. Andrews gaol, where he was confined a considerable time; their Court have repeatedly fined the inhabitants of these Islands for refusing to obey when summoned as jurymen, and they have taken several of their vessels laying close under those Islands, and carried them to St. John's [Saint John], where they detained them a considerable time before the owners could obtain their release. In the late instance, Capt. Dunn their High-Sheriff for Charlottee [Charlotte] County, with David Owen, Esq., one of their principal Magistrates, and four men, armed with muskets, pistols, &c. in a hostile and violent manner, went on Frederick Island, (above five miles west of what they call the river St. Croix, and attempted to break open Mr. DELESDERNIER'S house to search for property they said belonged to a British subject. Mr. Delesdernier opposing them, armed with an ax, prevented their succeeding on the house; but they finding a cow on the Island forcibly carried her off with them. Mr. Delesdernier not having any assistance, could not prevent it. Mr. Delesdernier is the collector of the Customs for the United States, and keeps his office in the house they endeavored to break open. - It is presumed, that Lord DORCHESTER, Governour General of the British Colonies in America, would not countenance such proceedings - but it is to be wished that measures may be speedily taken to prevent such insults in future.
The most intense of these "encroachments" would occur on July 14, 1814 when a British fleet under the command of Sir Thomas Masterman Hardy sailed from Halifax, Nova Scotia, captured Fort Sullivan on Moose Island [also known as Eastport, Maine] and renamed it Fort Sherbrooke after Sir John Coape Sherbrooke, then Lieutenant Governour of Nova Scotia.
Because the British had felt since the American Revolution that the islands of Passamaquoddy Bay were in their jurisdiction, they did not leave Moose Island at the end of the War of 1812 in 1815. After a few more years of negotiation, an agreement was reached on November 24, 1817 between the British representative Thomas Barclay, and the American, John Holmes, apportioning all of the islands in Passamaquoddy Bay to the British, except for Frederick, Dudley and Moose Islands, though the agreement still had to go through channels. The British left Moose Island in June 1818.
Though some townspeople refused to take the oath of allegiance and left, some just to the nearby mainland, where the British did not harrass them, most of those who stayed reportedly did not notice much difference between American and British rule in the areas of trade and daily life. Arguably, the influx of the British contributed to the cultural and social life.
While at Fort Sullivan/Sherbrooke, the British built a powder house that still stands, though in desperate need of restoration, a project that the Border Historical Society has ongoing.
Eastport, on Moose Island, and the islands of Passamaquoddy Bay: Moose Island is very close to the Perry, Maine, shore; the other two islands are now known as Treat Island and Dudley Island. Treat Island is managed by the Maine Coast Heritage Trust and is open to visitors.