The Great Divorce

Did you know St. Louis was almost the capital of the U.S.? At its peak, it was the 4th largest city in the country, booming in population and industry, and big enough that by 1904 it hosted the Olympics and the World’s Fair in the same year.

Many factors have contributed to the city’s decline over the following decades - white flight, highway development, redlining, and the economy shifting away from the river - from more than 850,000 residents in the 1950s to less than 300,000 now. One persistent structural issue underlying these events is the city-county split known as “The Great Divorce”.

A City Divided#

The City of St. Louis voted to separate from St. Louis County in 1876, becoming one of the few independent cities in America. Most other cities sit inside a county, like Chicago within Cook County, but St. Louis City and County are completely separate entities. This separation permanently froze the boundaries of St. Louis at 66 square miles**, which resulted in unforeseen consequences for the city.

St. Louis City and St. Louis County

Frozen borders#

Most other cities have continued to grow and expand over the last two hundred years - Chicago, for example, had dozens of annexations of its surrounding towns and villages between 1880 and now, during which it expanded from 36 square miles to 234 today. St. Louis remained at 66 square miles during that time.

Chicago and St. Louis size in square miles from 1880 to 2020

If St. Louis had followed in the footsteps of other cities, it would have absorbed many of the surrounding areas like Clayton, Maplewood, Richmond Heights, Webster Groves, and Kirkwood, but instead those are all separate cities.

Population stagnation#

As it stands, St. Louis City is not even close to being in the top 150 largest (by area), yet the Greater St. Louis area had the 21st highest population in the U.S. in 2020 (closer to 25th as of 2025 estimates).

St. Louis City and County population from 1880 to 2020

The suburbs have rapidly expanded over this time period, but the city has stagnated. This disparity has had an effect on the city’s reputation.

The Most Dangerous City?#

St. Louis has long been infamous for being the murder capital of the U.S. In 2024, St. Louis had the highest murder rate of U.S. cities. But while parts of St. Louis are legitimately dangerous, this stat doesn’t tell the whole story. St. Louis City only represents 10% of the population of its metro area - in stark contrast to the nearly 30% that Chicago represents, which is closer to the average.

City population as a share of its metro, 2020

Crime is reported by geographic boundary. Since St. Louis hasn’t expanded its borders in 150 years, its lower-crime suburbs fall outside the city borders and never enter the stats, so the rate reflects only the dense urban core, not the wider region.

Thought experiment#

If St. Louis City and County were to be one combined entity, what would the stats look like? I decided to add up the numbers to see how much of a difference it would make.

Measured across the city and county together, the homicide rate drops from 87 to 28 per 100k. Treating the combined STL City and County area as a single city is a bit contrived, but there are cities like San Antonio, Texas, which is a somewhat similarly sized city in both population and area.

St. Louis City + County compared with San Antonio, 2020

Even in this hypothetical scenario, the crime stats are still above the national average (which the FBI estimated at 6.5 in 2020) but much lower than St. Louis City alone. Among the 296 cities over 100,000 that reported 2020 data to the FBI, St. Louis City had the highest murder rate in the nation - the combined city (which I’ll call St. Loutopia) would instead rank roughly 15th, in the same range as Chicago and Richmond, Virginia.

Being honest though, this hypothetical city covers 570 square miles, which would make it one of the biggest cities in the U.S. (outside of Alaska). The city would become mostly sprawl to dilute St. Louis’s homicide rate down to still being within the top twenty most dangerous cities.

Where a combined St. Louis would rank among U.S. cities by land area, 2020

St. Loutopia would also be the 9th largest city in the 2020 census, about the same size in population as Dallas while covering roughly 230 more square miles of land.

Where a combined St. Louis would rank among U.S. cities by population, 2020

Recalculating the borders does not make the dangerous parts of the city any less dangerous, and that’s a serious problem. But nonetheless, St. Louis could be viewed in a more reasonable light if it was set up in a more comparable way to other metros.

Outlook#

Reunification has been attempted several times since the split. The most recent attempt, Better Together, was withdrawn in May 2019 before it ever reached a vote.

Louisville is one of the few cities to have merged with its county, as a case study.

An actual merger has not happened in 150 years (as of this writing), it does not seem likely that it will ever happen. There are legitimate concerns from both sides about such an event, and the city and county finding a way to work together would not immediately fix all problems from the last 150 years, but I believe anything that could improve the city’s reputation would be a win. A more unified region could also potentially work together better to solve these issues.

St. Louis will probably not ever be the 4th largest city in the U.S. again, (St. Loutopia might!) but if it wasn’t on the top of every “most dangerous city” list, I believe people would be more likely to visit and move here.

TL;DR#

• St. Louis City voted to separate from St. Louis County in 1876, freezing its borders at 66 square miles.
• The city peaked at 856,796 residents in 1950 and has shrunk every decade since, down to 301,578 in 2020. The county grew past a million during that time period.
• Crime is measured by city boundary, so the stats cover only the urban core. St. Louis (city) had the highest 2020 murder rate (87 per 100k) of the 296 large cities reporting to the FBI. The county was estimated around 10 per 100k.
• If the city and county were one merged city (St. Loutopia), it would be the 9th largest in the U.S. by population, roughly 4th by land area, and its murder rate would be 28, around 15th place. This doesn’t necessarily paint the best picture, because the city would need contain a massive amount of sprawl to bring down the statistics.
• Reunification attempts failed in 1926, 1959, 1962, and 2019.

Sources#

Every homicide count on this page comes from a single dataset for a single year: the FBI’s official 2020 “murder and nonnegligent manslaughter” figures. Rates are those counts divided by 2020 census populations.

• Crime in the U.S. 2020: Offenses Known to Law Enforcement - FBI Crime Data Explorer — murder counts for every reporting agency
• QuickFacts: St. Louis city and St. Louis County - U.S. Census Bureau, 2020 populations
• 2020 U.S. Gazetteer Files - U.S. Census Bureau — land areas
• TIGERweb - U.S. Census Bureau — the map’s city and county boundary outlines
• Demographics of St. Louis and St. Louis County, Missouri - census counts for the population-by-decade table

The St. Louis County total (104) is the St. Louis County Police Department (43) plus the 44 municipal police departments that reported to the FBI (61 combined). A handful of departments - Berkeley, Maryland Heights, and Webster Groves among them - did not report 2020 data, so the county figure is likely a slight undercount.

*There are 41 independent cities in the U.S. - 38 of them are in Virginia. The only ones outside it are St. Louis, Baltimore, and Carson City, Nevada.

**St. Louis’s 66 square miles includes about 4 square miles of the Mississippi River. City rankings compare land area, where the city measures 62.