Primacy

The city began its step toward national primacy as an important transportation hub between the eastern and western United States. Chicago's first railway, Galena and Chicago Union Railroad, opened in 1838, which also marked the opening of the Illinois and Michigan Canal. The canal allowed steamboats and sailing ships on the Great Lakes to connect to the Mississippi River. A flourishing economy brought residents from rural communities and immigrants abroad. Manufacturing and retail sectors became dominant among Midwestern cities, influencing the American economy, particularly in meatpacking, with the advent of the refrigerated rail car and the regional centrality of the city's Union Stock Yards.
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