IB History Canadian Prime Ministers Notes

The St. Lawrence Seaway (1954–1959)

Background and Causes

• After World War II, Canada wanted to grow its economy by improving trade and transportation. The St. Lawrence River, which connects the Great Lakes to the Atlantic Ocean, was seen as the key to expanding international shipping.
• For decades, Canada and the United States had discussed building a waterway deep enough for large ocean ships, but disagreements over funding and control delayed the project.
• By the 1950s, rapid industrial growth and increased trade made the project a national priority. Prime Minister Louis St. Laurent’s government decided to move forward, seeing it as a way to modernize the economy and strengthen relations with the U.S.
• Construction officially began in 1954 as a joint project between the two countries. The goal was to create a new route for ships carrying raw materials, manufactured goods, and grain between the Atlantic Ocean and central Canada.

Construction and Development

• The project was massive, stretching about 600 kilometers from Montreal to Lake Ontario. It included building locks, canals, and dams to allow ocean ships to travel safely through the Great Lakes system.
• Thousands of workers were employed on both sides of the border, and several towns were relocated to make room for the new waterway.
• The construction also created the Moses-Saunders Power Dam, which produced hydroelectric power shared between Canada and the U.S.
• When it opened in 1959, Queen Elizabeth II and U.S. President Dwight D. Eisenhower attended the inauguration, symbolizing the success of Canada-U.S. cooperation.

Impact and Legacy

• The Seaway became one of Canada’s greatest engineering achievements and a symbol of modernization and progress.
• It boosted international trade, allowing ships from around the world to reach inland cities like Montreal, Toronto, and even Chicago.
• The project also encouraged the growth of industries in central Canada by lowering shipping costs and improving access to markets.
• However, it raised concerns about American influence in Canadian trade and the environment, as parts of the river ecosystem were permanently changed.
• Despite criticism, the Seaway strengthened Canada’s economy, improved its global connections, and remains one of the most important trade routes in North America today.