Yellow fever and interracial marriages in New Orleans 1841

Approximately every third summer from 1817 until 1905, Yellow Fever plagued New Orleans killing almost 10% of the city each time. Fear fogged the air as patients experienced fevers, convulsions, and blood excreting from every cavity. The gruesome disease was spread by mosquitos, making the open barrels of water that were used for drinking and the hot and humid weather of the city a hot spot. Yellow Fever had a catch though, if you survive it, you become immune for life.

Ad for potential new cure to “secret disease,” referring to Yellow Fever. Taken from Times Picayune Newspaper. February 18, 1841.

As each summer brought on a new epidemic, Yellow Fever slowly changed the social hierarchies of New Orleans, including the hierarchy of marriage. It became about acclimated versus unacclimated rather than Anglo-American vs. Creole.

Because Creoles were mostly New Orleans natives, many had already contracted a mild form of the disease as a child and were now acclimated, along with slaves brought in from Haiti, as Yellow Fever raged on in the similar climate there, too. As German and Irish immigrants flooded New Orleans, raising the white population from 20,110 to 61,131 in just a decade, they also contracted Yellow Fever and died in huge numbers. Employers refused to hire white immigrants who could not prove they were acclimated, as there was little to gain from training a new employee only for them to die a few weeks later. Fathers rarely let their daughters marry unacclimated white immigrants and many neighborhoods did not allow these new immigrants to move in. Unless acclimated, a new white immigrant was excluded from the political and social economy of New Orleans.

Ad for runaway slaves. Taken from Times Picayune Newspaper, February 9, 1841.

Racial hierarchies were still in place though, with whites holding much more power than Black people, free or enslaved, and ads for runaway slaves still riddled the Times Picayune newspaper in 1841. Even still though, an acclimated slave would be priced 25-50% higher at the auction block. The disease became an argument used in support of white supremacy. Because the Anglo Immigrants were those most affected and killed at the highest rates, influxes of Black slaves were brought into New Orleans in an effort to protect Anglo immigrants from areas they may contract Yellow Fever. The false idea that all Black people were immune to Yellow Fever became widespread as well. It was the climate they had lived in, rather than their race, that increased the probability of a previous infection, making many Black people immune.

At the same time, New Orleans, in 1841, was one of the only Southern States to host a large population of free people of color: around 19%.  But what was special about New Orleans was the freed Black population owned property, amassed wealth, and played an essential role in the economy of the Crescent City, more so than any other state. By 1860, there were 472 free Black Louisianians with an average real estate holding of over $10,000. The state closest to that of Louisiana was South Carolina, who only had 162 free Black persons who held less than $5,000 of real estate holdings. New Orleans was one of the only main southern ports that had a greater toleration and acceptance of freed people of color, due to its French and Spanish rule.

In order for a species to survive, it must adapt to be able to have the highest chance at survival, mating, and producing an offspring. Therefore, a moth with a brown color that is able to hide amongst trees is more likely to survive than a bright colored moth, giving it a higher fitness. In humans, one way to increase fitness is to strengthen the immune system. Scientists have argued that our immunity genes, called major histocompatibility complex (MHCs), play a large role in how humans select a mate. The MHCs give each human their own unique “odorprint,” signaling to other members of the species what set of MHCs they have, as the sexual union of very different MHCs yields offspring with more diverse and robust immune systems. In a comparative survey of couples, scientist Bicalho and his team found that “real partners had significantly more MHC dissimilarities than we could have expected to find just by chance,” leading to the conclusion that humans have evolved to sniff out, literally, a fit partner.

Ad for work specifically for a man who is half white and half Black. Taken from Times Picayune Newspaper. February 26, 1841.

During a time of extreme racism and comparatively strict racial hierarchies, Yellow Fever acted as a catalyst, encouraging the union between the fit Black person and the susceptible Anglo-immigrant. Interracial marriages were illegal under New Orleans law, forcing each interracial union to be a consensual agreement. Because humans seek out those with a dissimilar immune system, in order to have a healthy offspring, in 1841 New Orleans, white men were seeking out Black women. In fact, in every decade between 1810 to 1840, interracial unions increased among the New Orleans population, and by 1840, around 14% of free Black women were in union with a white man, based on information gathered from wills.

With greater toleration of freed Black men and women came greater toleration of interracial unions. Compared to other surrounding states, the Black population of New Orleans was able to amass large amounts of wealth and dominate the skilled trade industry. Further, New Orleans was one of the only southern states with such a high population of interracial unions, as Americanized law had long been implemented elsewhere. However, even as New Orleans became more Americanized, with a growing white population and a shrinking freed people of color population, interracial unions persisted, subconsciously in order to keep the human species robust through the epidemic.

In 1841 New Orleans, the majority of the Black population, both enslaved and free, had become acclimated to Yellow Fever, leading to a stronger immune system. Because of the higher probability of acclimation, the Black population was the fittest population, making them the most attractive population to mate with. When choosing a mate in 1841 New Orleans, an unacclimated citizen would be better off mating with an acclimated citizen, producing an offspring with a potentially higher chance of surviving Yellow Fever, rather than another unacclimated citizen. Therefore, the newly arrived white immigrants were attracted to the Black population, a population with dissimilar MHCs, increasing the comparative rate of interracial marriages in New Orleans.