The border between the provinces of Quebec and of Newfoundland and Labrador is the longest interprovincial border in Canada. It stretches for more than on land, and, according to both provincial governments, also contains a maritime part. Starting from the north, the border follows the Laurentian Divide (the divide between the drainage basin of the Atlantic Ocean and of the Arctic Ocean) on the Labrador Peninsula for the majority of the border's length, then follows the divide between the Côte-Nord-Gaspé and Newfoundland-Labrador drainage basins as far as Brûlé Lake, after which it goes along the Romaine River downstream to the 52nd parallel, which it follows east to its southeastern terminus at Blanc-Sablon.
The division between Labrador and Quebec has changed over time. Labrador's coast has been recognized as part of Newfoundland since 1763 (except from 1774 to 1809), but the legal meaning of the word "coast" came to be disputed. A border dispute erupted in 1902 over the right to use natural resources in the Churchill River basin between the then dominions of Canada and Newfoundland. After lengthy delays, the case came before the Judicial Committee of the Privy Council in London, which in March 1927 delivered a win for Newfoundland and granted it the disputed land. The decision was further recognized by the governments of Canada and of Newfoundland when the latter joined Confederation in 1949 as the tenth province of Canada. The Privy Council described the line in general terms but it was never demarcated on the ground.
The government of Quebec disputes part of the boundary. Officials from this province argue and publish maps to the effect that the area of Labrador between the drainage basin divide and the 52nd parallel belongs to Quebec. At various times, the province's politicians alleged that the arbitration procedure was flawed and that the judges could have been biased, thus Newfoundland was awarded more territories than it specifically requested (). Legal scholars, however, are unconvinced by the accusations of bias and have suggested that only political negotiations might resolve the issue. The uncertain, winding border also made resource exploitation difficult, and separated mining and First Nations communities on either side of the border.
The maritime border's existence (and its delineation) is contested between the federal government and the provinces. According to Quebec, the Gulf of St. Lawrence is split equally between Quebec and Newfoundland; the latter says that there is some aquatic border but also argues that the 1964 agreement, which Quebec relies on and which was found to be non-binding in an arbitration case in 2001, was not ratified. Canada, in contrast, says that the waters belong to the federal government and therefore the boundary does not exist. In this respect, the jurisprudence of the Supreme Court of Canada supports the position of the federal government. This necessitates negotiation over the extent of exploitation of the natural resources and sharing of profits, in particular in relation to the Old Harry oil field.
Before 1927 The dependency of Labrador was created in 1763 and given to the colony of Newfoundland by a royal proclamation so that it could administer fishing rights. At that time, Labrador was limited to the coastal strip. Eleven years later, the Quebec Act 1774 gave the Province of Quebec control over all territories, islands and lands that had been appropriated to Newfoundland in 1763, but Newfoundland continued to regulate fishing. This created tensions between the colonies as Newfoundland no longer had any authority over the area. This state was short-lived because in 1809, Newfoundland got back the territories it lost in 1774 after lobbying in London. The southern border of Labrador was then defined by the British North America (Seigniorial Rights) Act 1825 (6 Geo. 4. c. 59). The act moved Lower Canada's border east from the Saint-Jean River to Blanc-Sablon. Lower Canada also gained territories from the coast up to the 52nd parallel north.
At Confederation, the Province of Canada was split in two. The eastern part, or Lower Canada, was renamed Quebec and became one of the four original provinces of the Dominion of Canada. Quebec's northern border was at the Laurentian Divide. That meant that it still shared the border with Labrador, a dependency of Newfoundland; however, the border was not clearly nor officially delimited.
Two expansions happened following Confederation. In 1898, Quebec and Canada adopted the Quebec Boundary Extension Act, 1898, which extended the northern frontier to the Eastmain River. This meant annexing a part of Labrador known as Ashuanipi (most of the southwestern part of the region); however, the area was not defined precisely, so the border remained officially undefined. Nine years later, Quebec requested an expansion of its territory further north to include the district of Ungava, which was granted by the Quebec Boundaries Extension Act, 1912. However, the act defined the border in the eastern part of Labrador as neighbouring the area "over which the island of Newfoundland has lawful jurisdiction", so it was not helpful to understand the precise course of the border. This border was also ambiguous as some islands were connected to the mainland at low tide, and thus the precise extent of the "Labrador shore" was unknown.
In 1924–25, the Dominion of Newfoundland proposed to sell interests in the eastern part of the peninsula to Quebec for million ($– million in dollars), but Quebec Premier Louis-Alexandre Taschereau refused. He believed that the territory lawfully belonged to Canada (and thus Quebec), and decided to wait for the Privy Council's decision. The government in St. John's then repeated its offer after a favourable Privy Council decision, this time to Canada, asking $110 million (equivalent to $ in dollars) for the land, but that deal was also rejected. When Newfoundland surrendered its autonomy to British authorities in 1934 due to the government's severe budgetary crisis, it was ready to sell Labrador again, but Quebec was not receptive. Just before joining Confederation, Newfoundland launched one more bid to sell Labrador, which a lot of Newfoundlanders found to be useless beyond the fishing rights the waters conferred, but it also failed.
Judicial determination of the boundary
In 1888, a trial judge in Labrador presided over a murder trial in which the defendant moved to dismiss the proceedings due to lack of jurisdiction. As a result, he advised his superiors in St. John's that the border of Labrador was not clearly defined and urged them to settle it, but the issue was not considered a high-priority one and was left for later resolution.
In 1902, a conflict erupted between Quebec, which was part of the Dominion of Canada, and Newfoundland, a colony of the United Kingdom, when Newfoundland issued a timber licence for a Nova Scotian company on the Churchill River. Quebec said the Quebec Boundary Extension Act, 1898 had granted them possession over most of Labrador and therefore the licence had to be issued by Quebec's authorities and had to conform to its laws. The company, on the other hand, contended that Newfoundland claimed all territories north of the 52nd parallel north and east of the 64th meridian west, so it did not violate anything. As the parties were unable to agree, Simon-Napoléon Parent, Quebec's minister of lands, mines and fisheries, asked the Canadian government to refer the question to the Judicial Committee of the Privy Council for arbitration. The governments of Canada and Newfoundland had agreed to do so by 1907, but it took them 15 years to agree to a common protocol. According to that set of rules, the Privy Council went on to determine "the location and definition of the boundary as between Canada and Newfoundland in the Labrador Peninsula under the statutes, orders-in-council and proclamations". The court was not tasked with drawing a new boundary, but only with issuing an interpretation of existing documents regulating Quebec's and Labrador's border to determine the possession of the Churchill River basin.
The stakes were high because of the large area of contested land (), but more importantly, forest resources estimated at $250 million ($ million in dollars) could be lost, or retained, depending on the perspective. Additionally, the Churchill Falls, then a full-blown waterfall higher than the Niagara, was in the area, which would prove to be an important asset in hydroelectricity.
Privy Council decision Oral arguments were held from late October to mid-November of 1926. According to L'actualité's analysis of documents of the , a government inquiry tasked with determining the soundness of Quebec's claims, Canada, which also represented Quebec, defended its claims very poorly. It first started arguing that the border did not exist at all even though its existence was an assumption upon which the arbitration had been launched. Canada then tried to demonstrate that proclamations only granted the Dominion of Newfoundland a strip of land extending from the coast so that it could control the coastal fisheries, while the inland parts of Labrador were part of Indian territory. That was despite the distance from Blanc-Sablon to the 52nd parallel (part of the frontier mentioned in the British North America (Seigniorial Rights) Act 1825) being . Canada also presented no evidence to the court of its numerous geological expeditions it had done to estimate the riches of the area and of the settlements of its citizens in Labrador's hinterland. This gave Newfoundland an edge in its arguments.
Newfoundland contended that the term "coast", which was used in communications with different governors, was meant to be more than just a narrow coastal strip, and that precedent showed that "coast" also referred to the drainage basin. The island's lawyers also showed documents confirming the government's presence in the area, including an agreement with the Hudson's Bay Company in which the company was obliged to pay royalties to Newfoundland for fur concessions located on the other side of the watershed (from HBC's point of view).
On 1 March 1927, the Judicial Committee issued a decision that sided with Newfoundland's interpretation of the border. It defined the frontier between Canada and Newfoundland as being:
The Privy Council ruled that the word "territory" (and not necessarily "coast"), as used in documents of the time, must have included a larger portion of the peninsula than Canada contended. At the same time, it made some corrections of the border that were not requested, as well as some errors. On the one hand, as Patrick McGrath noted, Canada's (and Quebec's) eastern border on the Gulf of St. Lawrence was moved eastward, effectively granting of land to Canada. On the other hand, Henri Dorion, a Quebec geographer, stated that Cape Chidley was on Killiniq Island, which has never been part of Quebec. At that time, it belonged to the Northwest Territories and now is part of Nunavut. Moreover, the Privy Council drew the line on the 52nd parallel north, rather than on the watershed. This made making the Council "recognize as Newfoundland's a territory bigger than it asked for, which in legal settings is called an ultra petita decision". The Council's border also divided the Innu and other First Nations, whose future it did not take into consideration.
As a result of such changes, the boundary between Quebec and Newfoundland and Labrador has become the longest interprovincial boundary in Canada, going for over .
Newfoundland enters Confederation When Newfoundland entered Confederation in March 1949, the Newfoundland Act (then known as British North America Act 1949) specified that