Saint Lawrence River in the context of "Beaver Wars"

The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Superior, Michigan, Huron, Erie, and Ontario (though hydrologically, Michigan and Huron are a single body of water, joined at the Straits of Mackinac). The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The lakes connect ultimately to the Atlantic Ocean via the Saint Lawrence River as their primary drainage outflow. The lakes are also connected to the Mississippi River basin through the Illinois Waterway.

The Great Lakes are the largest group of freshwater lakes on Earth by total area and the second-largest by total volume. They contain 21% of the world's surface fresh water by volume. The total surface is 94,250 square miles (244,106 km), and the total volume (measured at the low water datum) is 5,439 cubic miles (22,671 km), slightly less than the volume of Lake Baikal (5,666 cu mi or 23,615 km, 22–23% of the world's surface fresh water). Because of their sea-like characteristics, such as rolling waves, sustained winds, strong currents, great depths, and distant horizons, the five Great Lakes have long been called inland seas. Depending on how it is measured, by surface area, either Lake Superior or Lake Michigan–Huron is the second-largest lake in the world and the largest freshwater lake. Lake Michigan is the largest lake, by surface area, that is entirely within one country, the United States.

Ontario is the southernmost province of Canada. Located in Central Canada, Ontario is the country's most populous province. As of the 2021 Canadian census, it is home to 38.5% of the country's population, and is the second-largest province by total area (after Quebec). Ontario is Canada's fourth-largest jurisdiction in total area of all the Canadian provinces and territories. It is home to the nation's capital, Ottawa, and its most populous city, Toronto, which is Ontario's provincial capital.

Ontario is bordered by the province of Manitoba to the west, Hudson Bay and James Bay to the north, and Quebec to the east and northeast. To the south, it is bordered by the U.S. states of (from west to east) Minnesota, Michigan, Ohio, Pennsylvania (through Lake Erie), and New York. Almost all of Ontario's 2,700 km (1,700 mi) border with the United States follows rivers and lakes: from the westerly Lake of the Woods, eastward along the major rivers and lakes of the Great Lakes/Saint Lawrence River drainage system. There is only about 1 km (5⁄8 mi) of actual land border, made up of portages including Height of Land Portage on the Minnesota border.

Newfoundland (/ˈnjuːfən(d)lænd/ NEW-fən(d)-land, locally /ˌnuːfənˈlænd/ NEW-fən-LAND; French: Terre-Neuve, locally [taɛ̯ʁˈnœːv]) is a large island within the Canadian province of Newfoundland and Labrador. It is situated off the eastern coast of the North American mainland and the geographical region of Labrador.

The island contains 29 percent of the province's land area, but is home to over 90% of the province's population, with about 60% of the province's population located on the small southeastern Avalon Peninsula. The island is separated from the Labrador Peninsula by the Strait of Belle Isle and from Cape Breton Island by the Cabot Strait. It blocks the mouth of the Saint Lawrence River, creating the Gulf of Saint Lawrence, the world's largest estuary. Newfoundland's nearest neighbour is the French overseas collectivity of Saint Pierre and Miquelon. With an area of 108,860 square kilometres (42,031 sq mi), Newfoundland is the world's 16th-largest island, Canada's fourth-largest island, and the largest Canadian island outside the North.

New France was the territory colonized by France in North America, beginning with the exploration of the Gulf of Saint Lawrence by Jacques Cartier in 1534 and ending with the cession of New France to Great Britain and Spain in 1763 under the Treaty of Paris.

A vast viceroyalty, New France consisted of five colonies at its peak in 1712, each with its own administration: Canada, the most developed colony, which was divided into the districts of Quebec (around what is now called Quebec City), Trois-Rivières, and Montreal; Hudson Bay; Acadia in the northeast; Terre-Neuve on the island of Newfoundland; and Louisiana. It extended from Newfoundland to the Canadian Prairies and from Hudson Bay to the Gulf of Mexico, including all the Great Lakes of North America. The continent-traversing Saint Lawrence and Mississippi rivers were means of carrying French influence through much of North America.

Lake Ontario (French: Lac Ontario) is one of the five Great Lakes of North America. It is bounded on the north, west, and southwest by the Canadian province of Ontario, and on the south and east by the U.S. state of New York. The Canada–United States border spans the centre of the lake. On the Canadian side, the major cities are Kingston, Mississauga, Toronto, Hamilton, and St. Catharines. On the American side, the major cities are Rochester and Watertown.

The last in the Great Lakes chain, Lake Ontario serves as the outlet to the Atlantic Ocean via the Saint Lawrence River, comprising the western end of the Saint Lawrence Seaway. Its primary inlet is the Niagara River from Lake Erie. The Long Sault control dam, primarily along with the Moses-Saunders Power Dam regulates the water level of the lake.

The Great Lakes Basin consists of the Great Lakes and the surrounding lands of the states of Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin in the United States, and the province of Ontario in Canada, whose direct surface runoff and watersheds form a large drainage basin that feeds into the lakes. It is generally considered to also include a small area around and beyond Wolfe Island, Ontario, at the east end of Lake Ontario, which does not directly drain into the Great Lakes, but into the Saint Lawrence River.

The Basin is at the center of the Great Lakes region.

The Thousand Islands (French: Mille-Îles, pronounced [mil il]) constitute a North American archipelago of 1,864 islands that straddles the Canada–US border in the Saint Lawrence River as it emerges from the northeast corner of Lake Ontario. They stretch for about 50 miles (80 km) downstream from Kingston, Ontario. The Canadian islands are in the province of Ontario and the U.S. islands in the state of New York.

The islands range in size from over 40 square miles (100 km) to smaller islands occupied by a single residence, or uninhabited outcroppings of rocks. To count as one of the Thousand Islands, emergent land within the river channel must have at least one square foot (0.093 m) of land above water level year-round, and support at least two living trees.

Jacques Cartier (Breton: Jakez Karter; 31 December 1491 – 1 September 1557) was a French maritime explorer from Brittany. Jacques Cartier was the first European to describe and map the Gulf of Saint Lawrence and the shores of the Saint Lawrence River, which he named "The Country of Canadas" after the Iroquoian names for the two big settlements he saw at Stadacona (Quebec City) and at Hochelaga (Montreal Island).

Jacques Cartier, author of now-lost maps and accounts of his voyages, was the first European to describe and name this region and its inhabitants—at a time when the Spanish had already settled in the Caribbean, Mexico, and Central America, and were beginning their conquest of Peru.

While a variety of theories have been postulated for the name of Canada, its origin is now accepted as coming from the Laurentian language word kanata, meaning 'village' or 'settlement'. In 1535, indigenous inhabitants of the present-day Quebec City region used the word to direct French explorer Jacques Cartier to the village of Stadacona. Cartier later used the word Canada to refer not only to that particular village but to the entire area subject to Donnacona (the chief at Stadacona); by 1545, European books and maps had begun referring to this small region along the Saint Lawrence River as Canada.

From the 16th to the early 18th century, Canada referred to the part of New France that lay along the Saint Lawrence River. In 1791, the area became two British colonies called Upper Canada and Lower Canada. These two colonies were collectively named the Canadas until their union as the British Province of Canada in 1841.