District History
Explore how Missouri's congressional boundaries have shifted over two centuries. Use the timeline to jump between eras and click any district for election details.
Growth Era (1821–1870s)
Missouri entered the Union in 1821 with one at-large seat. Rapid westward expansion and population growth pushed the state from 1 district to 13 by the Civil War era. Early districts followed county lines and reflected Missouri's position as a gateway to the West.
Peak Representation (1870s–1930s)
Missouri peaked at 16 congressional districts in the 1870s–1900s, reflecting its status as one of America's most populous states. St. Louis was the 4th largest city in the nation. But relative population decline set in as the Sun Belt grew.
Reapportionment Revolution (1960s)
The Supreme Court's Baker v. Carr (1962) and Reynolds v. Sims (1964) decisions required equal-population districts nationwide. Missouri had to completely redraw its maps, ending decades of malapportioned rural districts. The state dropped from 11 to 10 seats.
Modern Era (2000–Present)
Missouri lost its 9th seat after the 2010 census, dropping to 8 districts. The current map features two heavily Democratic districts (1st in St. Louis, 5th in Kansas City) and six solidly Republican seats — a pattern driven by both geography and intentional line-drawing.