Question: When did the administrative territorial entity that contains the Sturgeon River become a province?

full_context: Document 1: Geography of Prince Edward Island: Prince Edward Island's geography is mostly pastoral with red soil, white sand, and scattered communities. Known as the "Garden of the Gulf", the island is located in the Gulf of Saint Lawrence north of Nova Scotia and east of New Brunswick, with which it forms the Northumberland Strait.
Document 2: Province House (Prince Edward Island): Province House is where the Prince Edward Island Legislature, known as the Legislative Assembly of Prince Edward Island, has met since 1847. The building is located at the intersection of Richmond and Great George Streets in Charlottetown; it is Canada's second-oldest seat of government.
Document 3: Charlottetown (electoral district): Charlottetown (formerly Hillsborough) is a federal electoral district in Prince Edward Island, Canada, that has been represented in the House of Commons of Canada since 2004. The district, which includes the entire City of Charlottetown, has an area of 46 km and a population of 34,562 as of 2011.
Document 4: Sturgeon River (Prince Edward Island): The Sturgeon River is a river in the Atlantic Ocean drainage basin in Kings County in eastern Prince Edward Island, Canada.
Document 5: Pictou Island (Nova Scotia): Pictou Island is a Canadian island located in the Northumberland Strait approximately 4 NM north of Nova Scotia and 10 NM south of Prince Edward Island. Measuring 9.5 km in length and 2.5 km in width, the total area is 23.75 km. The island is administratively part of Pictou County. The island's highest elevation is 24 meters (78 feet) above sea level, and its current full-time residents population (as of 2016) stands at 28, with the seasonal population rising and lowering.
Document 6: Saint Lawrence River: The Saint Lawrence River (French: Fleuve Saint - Laurent; Tuscarora: Kahnawáʼkye; Mohawk: Kaniatarowanenneh, meaning ``big waterway '') is a large river in the middle latitudes of North America. The Saint Lawrence River flows in a roughly north - easterly direction, connecting the Great Lakes with the Atlantic Ocean and forming the primary drainage outflow of the Great Lakes Basin. It traverses the Canadian provinces of Quebec and Ontario, and is part of the international boundary between Ontario, Canada, and the U.S. state of New York. This river also provides the basis of the commercial Saint Lawrence Seaway.
Document 7: Churchill, Prince Edward Island: Churchill is a community in the Canadian province of Prince Edward Island. The community was named for Winston Churchill. It is located in the township of Lot 65, Queens County immediately west of New Haven.
Document 8: Prince Edward Island: Prince Edward Island (PEI or P.E.I.; French: Île - du - Prince - Édouard) is a province of Canada consisting of the island of the same name, and several much smaller islands. Prince Edward Island is one of the three Maritime Provinces and is the smallest province in both land area and population. It is part of the traditional lands of the Mi'kmaq, and became a British colony in the 1700s and was federated into Canada as a province in 1873. Its capital is Charlottetown. According to the 2016 census, the province of Prince Edward Island has 142,907 residents.
Document 9: Brudenell, Prince Edward Island: Brudenell ( ) was a municipality that held community status in Prince Edward Island, Canada. It was located along the Brudenell and Montague Rivers. Brudenell Point, which is located at the confluence of the two rivers, was the site of the Jean Pierre Roma Acadian settlement in the 18th century. This small portion of Brudenell is now a National Historic Site of Canada called Roma Three Rivers. Before being burned to the ground by the English, among many accomplishments, this French settlement built several significant roads on PEI which are still used today.
Document 10: Prince Edward Island: Prince Edward Island Île - du - Prince - Édouard (French) Epekwitk (Mi'kmaq) Flag Coat of arms Motto (s): Latin: Parva sub ingenti (The small protected by the great) BC AB SK MB ON QC NB PE NS NL YT NT NU Confederation July 1, 1873 (8th) Capital Charlottetown Largest city Charlottetown Largest metro Charlottetown Government Lieutenant Governor Antoinette Perry Premier Wade MacLauchlan (Liberal) Legislature Legislative Assembly of Prince Edward Island Federal representation (in Canadian Parliament) House seats 4 of 338 (1.2%) Senate seats 4 of 105 (3.8%) Area Total 5,660 km (2,190 sq mi) Land 5,660 km (2,190 sq mi) Water 0 km (0 sq mi) 0% Area rank Ranked 13th 0.1% of Canada Population (2016) Total 142,907 Estimate (2018 Q1) 152,768 Rank Ranked 10th Density 25.25 / km (65.4 / sq mi) Demonym (s) Prince Edward Islander, Islander Official languages English (de facto) GDP Rank 10th Total (2011) C $5.353 billion Per capita C $36,740 (13th) Time zone Atlantic: UTC - 4 Postal abbr. PE Postal code prefix ISO 3166 code CA - PE Flower Pink lady's slipper Tree Red oak Bird Blue jay Website www.princeedwardisland.ca Rankings include all provinces and territories
Document 11: Belfast-Murray River: Belfast-Murray River is a provincial electoral district for the Legislative Assembly of Prince Edward Island, Canada. Created mostly from 4th Kings, part of 5th Kings and a small part of 4th Queens in 1996. It was formerly named Murray River-Gaspereaux from 1996 to 2007.
Document 12: Lennox Island (Prince Edward Island): Lennox Island is an island located in Malpeque Bay off the northwest coast of Prince Edward Island, Canada. Connected by a short causeway and bridge, Lennox Island is home to the Lennox Island First Nation, of the Mi'kmaq people. The Mi'kmaq name for the island was "L'nui Minegoo", and it has been informally known by European settlers as "Indian Island".
Document 13: Cann River: The Cann River rises southwest of Granite Mountain in remote country on the eastern boundary of the Errinundra National Park and flows generally east, then south, then east, then south through the western edge of the Coopracambra National Park and through the Croajingolong National Park, joined by seventeen minor tributaries before reaching its mouth with Bass Strait, at the Tamboon Inlet in the Shire of East Gippsland. The river descends over its course.
Document 14: East River, Nova Scotia: East River is a community in the Canadian province of Nova Scotia, located in the Chester Municipal District on the Aspotogan Peninsula on the Lighthouse Route at the junction of (Nova Scotia Route 329) and Trunk 3.
Document 15: Lake of Bays River: The Lake of Bays River is a river in Kenora District in Northwestern Ontario, Canada. It is in the Hudson Bay drainage basin and is a left tributary of the Sturgeon River.
ground_truth: 1873
sub_queries: Sturgeon River >> located in the administrative territorial entity Answer: Prince Edward Island
when did Prince Edward Island become a province Answer: 1873