1900s

-creation of International Harvester from these companies in 1902 capped Chicago's leading position in this industry.

1950s
-economy experienced competition with Detroit
- building of the interstate highway system in the 1950s and 1960s helped the area's economy initially, because the first expressways paralleled existing forms of transportation and reinforced older metropolitan areas. 
-Although the area's industrial economy remained strong, the city's did not. Companies closed aging factories in the city and shifted work to new suburban plants
-As jobs became more plentiful outside the city, people migrating to the Chicago area often settled in the suburbs, bypassing the city entirely. This was only true, however, if the migrants were white; because of discrimination, African Americans were restricted to the city.