The Canadas is the collective name for Upper Canada

Upper Canada

The Province of Upper Canada was a political division in British Canada established in 1791 by the British Empire to govern the central third of the lands in British North America and to accommodate Loyalist refugees from the United States of America after the American Revolution...

and Lower Canada

Lower Canada

The Province of Lower Canada was a British colony on the lower Saint Lawrence River and the shores of the Gulf of Saint Lawrence...

, two British colonies

British colonization of the Americas

British colonization of the Americas began in 1607 in Jamestown, Virginia and reached its peak when colonies had been established throughout the Americas...

 in Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. They were both created by the Constitutional Act of 1791

Constitutional Act of 1791

The Constitutional Act of 1791, formally The Clergy Endowments Act, 1791 , is an Act of the Parliament of Great Britain...

 and abolished in 1841 with the union of Upper and Lower Canada

Union of Upper and Lower Canada

The Union of Upper and Lower Canada created the Province of Canada in 1841. This province lasted until 1867 when Canadian Confederation encouraged the two groups to split again into the Canadian provinces of Ontario and Quebec- Upper and Lower Canada :...

.

Their names reflected their positions relative to the headwaters of the St. Lawrence River, the same relationship between Upper Egypt

Upper Egypt

Upper Egypt is the strip of land, on both sides of the Nile valley, that extends from the cataract boundaries of modern-day Aswan north to the area between El-Ayait and Zawyet Dahshur . The northern section of Upper Egypt, between El-Ayait and Sohag is sometimes known as Middle Egypt...

 and Lower Egypt

Lower Egypt

Lower Egypt is the northern-most section of Egypt. It refers to the fertile Nile Delta region, which stretches from the area between El-Aiyat and Zawyet Dahshur, south of modern-day Cairo, and the Mediterranean Sea....

:

• Lower Canada covered the south-eastern portion of the modern-day Province of Quebec
  Quebec
  Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
  
  , Canada, and (until 1809) the Labrador
  Labrador
  Labrador is the distinct, northerly region of the Canadian province of Newfoundland and Labrador. It comprises the mainland portion of the province, separated from the island of Newfoundland by the Strait of Belle Isle...
  
   region of the modern-day Province of Newfoundland and Labrador
  Newfoundland and Labrador
  Newfoundland and Labrador is the easternmost province of Canada. Situated in the country's Atlantic region, it incorporates the island of Newfoundland and mainland Labrador with a combined area of . As of April 2011, the province's estimated population is 508,400...
  
  
• Upper Canada covered what is now the southern portion of the Province of Ontario
  Ontario
  Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
  
   in Canada, and the lands bordering Georgian Bay
  Georgian Bay
  Georgian Bay is a large bay of Lake Huron, located entirely within Ontario, Canada...
  
   and Lake Superior
  Lake Superior
  Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...
  
  .
• The northern part of the current provinces of Ontario and Quebec were at this time part of Rupert's Land
  Rupert's Land
  Rupert's Land, or Prince Rupert's Land, was a territory in British North America, consisting of the Hudson Bay drainage basin that was nominally owned by the Hudson's Bay Company for 200 years from 1670 to 1870, although numerous aboriginal groups lived in the same territory and disputed the...
  
  .

History

The British colony of the Province of Quebec was divided by the Constitutional Act of 1791 into two separate provinces, with the Ottawa River

Ottawa River

The Ottawa River is a river in the Canadian provinces of Ontario and Quebec. For most of its length, it now defines the border between these two provinces.-Geography:...

 forming a part of the border.

The creation of Upper Canada was in response to the desire expressed by recently arrived United Empire Loyalist settlers for British institutions and laws, especially British laws of land tenure.

The political structure of the colonies was changed after Lord Durham's

John Lambton, 1st Earl of Durham

John George Lambton, 1st Earl of Durham GCB, PC , also known as "Radical Jack" and commonly referred to in history texts simply as Lord Durham, was a British Whig statesman, colonial administrator, Governor General and high commissioner of British North America...

 1838 Report on the Affairs of British North America recommended they be merged into a single colonial province.

Lower Canada, Upper Canada and their legislatures were abolished by the British Act of Union 1840

Act of Union 1840

The Act of Union, formally the The British North America Act, 1840 , was enacted in July 1840 and proclaimed 10 February 1841. It abolished the legislatures of Lower Canada and Upper Canada and established a new political entity, the Province of Canada to replace them...

 of July 23, 1840 (which came into force in early 1841) and united as one political entity, the Province of Canada

Province of Canada

The Province of Canada, United Province of Canada, or the United Canadas was a British colony in North America from 1841 to 1867. Its formation reflected recommendations made by John Lambton, 1st Earl of Durham in the Report on the Affairs of British North America following the Rebellions of...

.