How Yellow Fever Intensified Racial Inequality in 19th-Century New Orleans

A new book explores how immunity to the disease created opportunities for white, but not Black, people

A 19th-century illustration of two yellow fever victims in New Orleans
A 19th-century illustration of two yellow fever victims in New Orleans Bettmann / Getty Images

More than two years into the Covid-19 pandemic, the social, economic and political implications of public health crises are more apparent than ever—as is the fact that people of color and poorer communities often bear the brunt of these contagions’ consequences.

A new analysis of yellow fever in antebellum New Orleans highlights striking parallels with the ongoing pandemic, illustrating how the mosquito-borne virus interacted with the Louisiana capital’s unique climate, cotton-driven economy and violently exploitative labor regime to spark wave after wave of epidemics. Against a backdrop of intensifying slavery, yellow fever transformed New Orleans into a city of the dead, claiming as many as 150,000 lives between 1803 and the outbreak of the Civil War. The disease also created a horrific form of what Kathryn Olivarius, a historian at Stanford University, describes as “immunocapitalism”: a “socially acknowledged lifelong immunity to a highly lethal virus, providing access to previously inaccessible realms of ... power.”

Necropolis: Disease, Power, and Capitalism in the Cotton Kingdom

Disease is thought to be a great leveler of humanity, but in antebellum New Orleans acquiring immunity from the scourge of yellow fever magnified the brutal inequities of slave-powered capitalism.

In her book Necropolis: Disease, Power, and Capitalism in the Cotton Kingdom, out now from Harvard University Press, Olivarius explores the racialized nature of New Orleans’ yellow fever epidemic. For the disease-ridden city’s 19th-century populace, immunity was the key to opportunity, determining where locals lived and worked, who they socialized with, and other aspects of daily life. Because people had no way of proving their immunity in this pre-vaccine world, accruing “immunocapital” was more about convincing others of one’s status than actually being immune to yellow fever. This immunity—whether real or perceived—had wildly conflicting implications for white Orleanians and enslaved Black people.

At the time, medical professionals erroneously believed that African people were immune to yellow fever—a theory that was used, in turn, to justify racial slavery. Slaveholders reasoned that “God intended for enslaved people to be enslaved, specifically in the American South, ... because the cotton economy would entirely collapse without the labor of immune Black people,” says Olivarius. “Many pro-slavery theorists and doctors essentially were saying that Black slavery was positively humanitarian, because it distanced white people, who would be vulnerable to yellow fever, from labor and spaces that would kill them, whereas Black people could safely work in these spaces.”

Smithsonian chatted with Olivarius about yellow fever in New Orleans, how surviving the disease played out differently for white and Black people, and what it was like to write about the history of racism and disease in the midst of a pandemic. Read a condensed and edited version of the conversation below.

What is yellow fever, and how is it different from Covid-19?

Yellow fever is very, very different from Covid-19. It’s an acute hemorrhagic fever spread by mosquitoes, and in the 19th century and earlier, it was the most terrifying disease in the Atlantic world. This was the disease that kept people up at night, because it was a miserable way to die. Victims experienced a sudden onset of nausea and chills, muscle pains, back aches, and jaundice. Within days, patients would be oozing blood through their orifices. They vomited up partly coagulated blood with the consistency and color of coffee grounds. They could lapse into a coma and die of organ failure. Even the most pious victims—ministers, priests—were screaming profanities as the end neared. It was that painful.

Illustration showing the development of yellow fever in a patient in Cadiz, Spain, in 1819
Illustration showing the development of yellow fever in a patient in Cadiz, Spain, in 1819 Public domain via Wellcome Collection

Yellow fever was terrifying because it was so mysterious. Even the most experienced doctors were flummoxed. There was no cure, no inoculation, no satisfactory explanation for why it killed some people and spared others. It was only at the end of the 19th century that Cuban researchers discovered yellow fever’s vector, the female Aedes aegypti mosquito, and only in the 1930s that an effective vaccine was developed.

How did people at the time understand and treat this deadly disease?

The full impact of yellow fever is hard to calculate because at the time, they bent over backward to not come to grips with the enormity of any epidemic. Every second or third year, an epidemic would strike, and during those epidemics, as many as 8 percent of the population could die. In some immigrant neighborhoods, especially German and Irish ones, epidemics killed off 20 percent of people. In 1853, the year of the worst epidemic in New Orleans, with over 12,000 deaths, about 10 percent of the city’s population died. And one-fifth of the Irish-born population died.

Though little was known about how the virus spread or how and why it was so deadly, people certainly recognized some patterns of transmission and sickness in yellow fever. They understood that yellow fever struck during a fairly well-defined fever season, roughly July to October. They [mistakenly] thought that yellow fever was miasmatic, the organic result of the city’s heat, meteorology, soil and climate. [The now-obsolete miasma theory posits that diseases are caused by miasma, an ancient Greek word that translates roughly to pollution.] It sort of makes sense, because in the summertime, thick, hazy steam arose from the ground, and people actually talked about it as if it had a tangible quality.

Locals called yellow fever a “strangers’ disease,” associating it with foreign-born, poor and hard-drinking folks. Contemporary science also held that all Black people were less impacted by yellow fever than white people, either because they were hereditarily immune or extremely resistant to the virus. This wasn’t true, but the idea stuck. Most of all, 19th-century Southerners had a very strong conception of acclimation, the process by which someone becomes sick with yellow fever, survives and acquires immunity. They had a sense that if someone had been around long enough, they became immune to the disease.

What is immunocapital?

To possess what I call immunocapital, a person in New Orleans had to convince others of their immunity status. They could then leverage that immunity for material gain, whether professional, economic or social. Immunocapitalism is the system of class rule in which disease and immunity were used by the elites to justify vast inequality.

There were occasionally laws that it was illegal to sell unacclimated people in the New Orleans slave market because it was just too risky. These laws were flagrantly ignored, but you can see how important the acclimation credential was even in the buying and selling of human beings.

What made New Orleans such a special—and susceptible—city?

New Orleans is an extraordinary city now, and it was an extraordinary city then. It’s located about 15 feet from the river’s edge, and most of the city sits about just one foot above sea level. So, this is basically a very swampy place, and water has always been this difficult factor: water from the sky, from hurricanes, from the river, from groundwater seeping up. [New Orleans’ wet environment proved to be the perfect breeding ground for the mosquitoes that spread yellow fever.]

An engraving of enslaved people being sold in New Orleans in the rotunda of St. Charles Hotel around 1839
An engraving of enslaved people being sold in New Orleans in the rotunda of St. Charles Hotel around 1839 Photo by Fotosearch / Getty Images

In the 18th century, New Orleans was controlled alternatively by the French and the Spanish. Colonial officials often wrote back to Europe, saying this city isn’t tenable in the long term. But all that changed in the 1790s because of two things: cotton and sugar. In 1796, sugar was planted successfully for the first time in Louisiana. This set off a chain reaction, and suddenly all these sugar mills started popping up along the lower Mississippi River. Sugar was an incredibly lucrative crop for white planters and enslavers, who used slave labor to cut cane, boil it and refine it into sugar. And cotton became a viable product in this very, very rich soil of the Mississippi Delta, all the way up to Arkansas, Texas, Kentucky, Tennessee and Alabama. The cotton gin increased productivity by a factor of 50. Of course, cotton was also slave-grown.

New Orleans would not exist without slavery. It was integral to the development and prosperity of the city. At the same time that cotton and sugar are on the rise, slavery is on the rise, and New Orleans is on the rise. Once these crops were successful, people started absolutely pouring into New Orleans, and the city was growing very, very quickly. After the Louisiana Purchase in 1803, Americans took over control of the city, and New Orleans became the largest hub for America’s domestic slave trade.

How was race connected to discussions of yellow fever and immunity?

The notion that Black people, no matter where they had been born or where they were from, were inherently more resistant or entirely immune to yellow fever had deep roots in the Atlantic world. This idea wasn’t invented in New Orleans or in the American South. It had been present in the Greater Caribbean, and really since the first outbreaks of yellow fever in the 17th century in Barbados. But it really took off in the American South.

One of the ideological justifications for racial slavery expansion becomes that Black people are immune to yellow fever. ... You see this not just with yellow fever but also cholera, which periodically ripped through the South. Enslavers were absolutely petrified that this would quite literally destroy them by killing their capital [in other words, enslaved people]. On the one hand, the public line from these enslavers is that Black people are immune to yellow fever, but on the other, no self-respecting purchaser of enslaved people would ever purchase a person in New Orleans without an express guarantee of acclimation.

What was the public health response to the constancy and intensity of yellow fever outbreaks?

Public health could scarcely have been worse in New Orleans. They had basically no board of health that was tasked with tracking or defining disease. Sanitation was very, very minimal. In the years that a board of health did exist, it might collect some data. But most years, there was no single body tasked with tracking or defining disease or even quantifying it. No epidemic before 1817 was counted. Records always undercounted enslaved people, who almost never appear in the mortality record when it comes to yellow fever. Some years, officials would also remove seafarers or other groups from the lists of the dead, artificially minimizing the numbers even more.

Another big thing is that New Orleans didn’t implement quarantines, which are basically the most powerful weapon in a health officer’s arsenal. Nobody really likes quarantines, and businesses especially hate quarantines. In New Orleans, quarantines were a non-starter. They were implemented only a few times, very briefly, during the entire antebellum period. This was in stark contrast to other American cities at the time that were basically enhancing their quarantine infrastructure with every successive year. New York, Philadelphia and even Charleston had not just a single quarantine station, but often many quarantine stations to deal with different kinds of diseases. Over the course of the 19th century, these cities are really trying to take more control over the public’s welfare, consolidating their power over questions of health and trying to depoliticize the issue. In New Orleans, that just doesn’t happen.

A horse-drawn ambulance photographed during a 1905 outbreak of yellow fever in New Orleans
A horse-drawn ambulance photographed during a 1905 outbreak of yellow fever in New Orleans Public domain via Wikimedia Commons

So, why wasn’t this a leading political issue? That’s a question I find perpetually fascinating. Why weren’t there protests on the streets from people saying clean up the city? There was this fascinating process with most townspeople, in which they would protest the situation early on after they moved to New Orleans. Then, they either came to accept it, they fled the city, they died, or they survived and became acclimated. Once they’re an acclimated citizen, they align their interests with the rest of their epidemiological class.

What was it like writing about epidemics during the Covid-19 pandemic?

It wasn’t ideal. At times, life imitated art to an eerie degree, in ways that could be overwhelming and stressful. There’s this dual tempo of fervent activity and fear, coupled with ennui or melancholy. You can also see that in how people reacted in the past. I feel almost glad to have experienced something at least similar to what they experienced.

One aspect that really resonated early on in the pandemic was the false debate between locking down or keeping the economy open. That was always a false dichotomy in some sense, because do you prioritize the public’s health or the economy? You had politicians saying it’s basically your patriotic duty as an American to not live in fear of this virus, to get out there, to go back to work, to keep our economy buoyant. The way this was politicized, and this notion that facing the disease, getting sick with it and recovering was somehow a patriotic act—there are some deep echoes of the antebellum period with that.

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