Glowing red network of blood vessels against a black background.

According to Western science, blood is both a fluid and a tissue. It is composed of blood cells and plasma, the liquid that surrounds those cells. Blood brings nourishment to the whole body, carries hormones, protects and supports the body as part of the immune system, and helps to warm us when we are cold and cool us when we are hot (Cleveland Clinic, 2023). Blood has its own history, its own rhythm and memory. It’s an expression of life.

Blood has also been layered with cultural meanings beyond its physical form. In this story, we look at how blood came to be used (without consent) as a tool of oppression and harm – of sorting, categorization, and value.

Like most of the wounds brought to this land, oppressive ideas about blood in the U.S. today originated in Europe. In the Greek Empire, blood was viewed as a symbol of strength and the place where “purity” lives. Blood spilled in battle was seen as sacred and the sign of ultimate bravery. Menstrual blood and the blood from dead and preserved bodies (both human and animal) were considered “impure” blood. After Christianity emerged and eventually became the state religion of the Roman Empire, the idea that “pure blood” comes from sacrifice frequently showed up in stories of Christian saints and martyrs. This framework was also woven into anti-Jewish oppression through the “blood libel” myth (Facing History, 2022) and the idea that Jews had dangerous and impure blood. This solidified the belief that Christian blood alone is “pure,” a belief which fueled the colonizing forces of the Catholic Crusades.

Medieval illuminated manuscript illustration showing a physician performing bloodletting on a seated patient.

Early Western medicine saw illness as an imbalance of fluids in the body, with treatment focused on bringing balance between these fluids. Bloodletting, whether through leeches or cutting, was a primary form of medical treatment across cultures surrounding the Mediterranean for thousands of years - until well into the 1800s (Cohen, 2018). Bloodletting was based on the belief that releasing “bad” blood allows more space for the “good,” which became linked to ideas of race.

The idea of blood as being either “pure” or “impure” was carried by colonizers to Turtle Island and used to define and defend laws of surveillance and property. In 1705, the Virginia Slave Codes attempted to define who could be legally enslaved. Prior to the Atlantic Slave Trade, people were most often enslaved after being captured in battle. Under the Virginia Slave Codes, enslavement became something that a person could inherit, as it was tied to physical characteristics, specifically to people of African descent. Unlike previous forms of enslavement, this status could no longer be removed through “good works” or payment of a perceived debt.

The Virginia Slave Codes framed the terms of enslavement as “essential” or “biological” rather than primarily cultural, political, or economic. They made slavery permanent for "Negroes, Mulattos and Indians," defining these people, literally, as "real estate:” less than human property that could be owned and controlled. This system was rooted in beliefs about blood, as the Slave Codes defined “Negro” people as anyone who had 1/8 African parentage and Indian people as anyone with 1/2 Native parentage. These laws were the origin of the “one drop” rule for African ancestry and the “blood quantum” rule for Indigenous people.

An early treaty between the US government and the Osage tribe first introduced land allotment and federal policy based on "blood degree” (DesJarlait, 2021). Historically, tribal membership was based on a tribe's own cultural traditions. In the early United States, treaty negotiations generally recognized and accepted tribal language, customs, and authority, even while taking land through violence. However, once the US was no longer dependent on recognition from tribal nations to cement its own legitimacy, the strategy moved from cultural recognition to cultural disappearance.

“Blood quantum” policies regulate the number of people who can claim tribal membership based on their quantity of blood from a specific community. The US government continues to base program eligibility (and therefore access to treaty agreements) on tribal blood percentages today. This means that even with eight Native great-grandparents, a person’s eligibility for tribal membership is based on the percentage of blood that they carry from a single tribe. Through this practice, the US government has been able to limit the number of people eligible for specific services agreed upon by treaty, such as healthcare, food, access to education and more. Many Native communities refuse to recognize “blood quantum,” even when it means giving up their rights granted through treaty.

During the same period, the “one drop rule” was used to entrench white supremacy (Blay, 2021). Whiteness was centered and protected as a mark of “pure blood,” while the blood from Black bodies was seen as “impure.” Maintaining this clear and literal color line was used to justify the concentration of power under whiteness: anyone with even “one drop” of Black blood was - and sometimes still is - considered a threat to the white race. Many racist cultural and legal practices in the US are built on the perception that Black bodies are “dangerous,” with a predilection for “criminality.”

Proving that whiteness needed to be “protected” from “dangerous blood” became one of the central organizing strategies of scientific racism of the 1800s. Anti-miscegenation laws crystallized fears about “mixing” blood through interracial marriage and relationships (Cruz & Berson, 2001). Sometimes these laws went beyond marriage to make any sexual union between people of a different race illegal, although most often they specified relationships between Black and white people. The “one drop rule” attempted to turn race into a biological fact rather than a social construct, something that could be passed down from one generation to the next. Over the centuries, the language shifted between “European,” “white,” “Anglo-Saxon” and “Christian,” but the belief remained that “white blood” needed to be protected in order to preserve social status, property, and Christian faith.

Black-and-white photograph of protesters at a march holding signs reading “Inter-racial Marriage Club of Washington, D.C., naturally wants Freedom Now” and “My home is desegregated & good.”

In the late 1700s and early 1800s, many physicians in the United States believed that Blackness was a state of being that could be passed from Black people to white people. Whiteness, they said, must be protected. Physicians such as Benjamin Rush saw Blackness as a series of characteristics that could be assessed, diagnosed and then treated (Willoughby, 2017). Because white supremacy is flexible and often contradictory, these perceived characteristics ranged from “lazy and undisciplined” to “dangerous and fierce.” Many doctors believed that Blackness could be “cured” by figuring out the right physical approach. Their strategies were various: from disappearance (genocide and/or assimilation) to institutionalization and segregation.

In "Hints on the Medical Treatment of Negroes," medical student Moses McCloud stated that "heroic treatments" such as bloodletting would strengthen a white body and weaken a Black body (Willoughby, 2017). For this reason, he wrote, all such treatment should be withheld from sick Black people so as to not "weaken" them. McCloud was not alone at the time in calling for separate, racialized medical systems for treating white and Black patients. This ideology was rooted in a belief in biological differences between Black and white bodies linked to different ancestral environments. McCloud also promoted racialized myths about differences in pain tolerance; similar “biological” language was used to justify both enslavement and then later, Black poverty. This belief in an essential racial difference in pain tolerance is unfortunately not an “old-fashioned” sentiment: it is still baked into the algorithms of today’s medical diagnostic software (Grant, 2022).

With the colonization of Turtle Island, the European belief that a person’s essential qualities are carried in their body and blood and determine their overall “humanity” (based on a white/European/Christian standard) were woven into the development of science and medicine. Racialized notions of “good” and “bad” (or “safe” and “dangerous”) blood have shown up throughout US history, targeting multiple communities. In the 1870s, white doctors on the West Coast blamed members of the Chinese community for the rise in venereal disease in the white community, stoked by the racist myth of a “yellow peril.” In San Francisco, the founder of the University of California Medical School publicly blamed Chinese sex workers for being "the source of the most terrible pollution of the blood of the younger and rising generations" (Trauner, 1978).

The examples continue:

In 1922, when sickle-cell anemia was first identified and observed as occurring at higher numbers in African-American communities, it was named as evidence of Black blood being dangerous and used to bolster arguments against interracial relationships (Wailoo, 1996).
In the early 1920s, many states passed laws that banned relationships across race, not only between white and non-white people. Louisiana banned marriage between Native American & African Americans in 1920.
In the Racial Integrity Act of 1924, which expanded on the logic of the Virginia Slave Codes, Virginia specified that "one drop" of African-descended blood was enough to prohibit a Black or mixed race person from marrying a white person.

Historical photograph of six Black men who participated in the Tuskegee Syphilis Study, standing together outdoors.

In 1932, researchers for the Tuskegee Syphilis Study told the people participating in the study that they were being treated for "bad blood,” when they had actually contracted syphilis. At the start of the study, there was no known treatment for syphilis. The participants (mostly men and a few women) were told that the study would last about six months, but it went on for years. When penicillin became the standard treatment for syphilis, it was withheld from the participants in order to prolong the study. Those participating were never taken through the standard protocol of informed consent, told the actual name of the study, or alerted to the potentially life-threatening impact of the treatment they would receive. They were not informed of the impacts of syphilis on themselves or their family members or they were not given the choice to quit the study once penicillin became available. At least 600 Black participants and their families were impacted (Tuskegee University, n.d.).
In 1934, the Indian Reorganization (“Wheeler-Howard”) Act created land allotment and "encouraged" tribal self-government by replacing traditional forms of government with Western hierarchical systems. Tribes who wanted federal recognition were forced to adopt constitutions following government guidelines, including membership based upon "blood" degree. In exchange, the federal government agreed to prohibit further allotment of Native land, provide support for college tuition, and a range of other agreements. Some tribes saw the Act as beneficial, in particular its clarity about tribal self-government (within a prescribed system), while others fought back against separation from traditional forms of governance (MCTG, n.d.).
In 1937, the first official blood bank, the Cook County Hospital in Chicago, began the practice of blood segregation, separating blood donations by race and matching donors to patients of the same race. In 1942, the American Red Cross continued this practice by mandating that blood donations had to be separated by “race,” only stopping this practice in 1950 (Zimmerman, 2022).

While contemporary science no longer explicitly references “good” versus “bad” blood, this ideology continues in the shadows, subtly influencing how white supremacy and surveillance culture show up in our institutions. The school-to-prison pipeline perpetuates ideas about “dangerous bodies” through the criminalization of BIPOC youth. Different bodies are assigned this role based on contemporary politics, with racist myths cemented through popular culture. Latine and Arab and Muslim people have become increasingly labelled as “dangerous bodies” today.

A gloved hand holds a test tube of blood in front of a graphic of a DNA double helix.

Being able to track and control “criminal bodies” and “criminal blood” is at the core of most state surveillance strategies. Some elements of these practices have changed, while others remain the same. In 1991, a group of incarcerated people in Virginia filed a case against the mandatory collection of their DNA, and a federal court upheld the statute requiring mandatory blood samples from all who are convicted of a crime. The court argued that “felons” have no privacy rights that prevent this collection, and that the government must protect the public by using incarcerated peoples’ blood to help identify if they commit additional “crimes.”

The Violent Crime Control and Law Enforcement Act of 1994 expanded the use of DNA collection for criminal convictions (Nelkin & Andrews, 1999). The Act provided funds for local areas to build capacity for DNA testing. As a result of this increased funding, all 50 states now have laws mandating blood collection from at least some of the people convicted of a crime. Access to DNA testing only runs in one direction, however - in 2009, the Supreme Court ruled that incarcerated people do not have a constitutional right to request DNA testing to prove their innocence.

Astronomical image of a glowing star surrounded by a nebula against a starry sky.

In addition to being a site of surveillance for “dangerous bodies,” blood has also become commodified as a product to buy and sell. The United States is often referred to as the "OPEC of blood,” providing half of the European supply of plasma, which amounts to $19 billion in annual profit (Ferranti, 2018). The majority of people who sell blood are living in poverty in the US. Under racial capitalism, this means a disproportionate number of people selling their blood to pay their basic bills are Black, Brown, and Indigenous people. In the 1990s, the Arkansas state prison system also came under scrutiny for selling plasma from incarcerated people, a common practice in this state and others since the 1960s (CALS, n.d.).

Blood has its own material presence. If you close your eyes and invite your blood to rise up and show itself, you may feel your body warming. If you are looking in the mirror, you may see a shift in your skin color as the blood comes closer to the surface. The minerals in your blood come from the land around you, from the air you breathe, and from the bodies of the ancestors that created your own body.

One of the primary elements of blood is iron. Iron is what is produced when a red giant star goes through an atomic shift. When most of the star becomes iron, it explodes, sending that iron spinning into space, eventually combining with other elements to form planets and meteors and other solid forms. The majority of the iron in your body is found in the blood in the form of hemoglobin. Some is held in the muscle fibers. We could not live without the interplay between iron and oxygen. The reality of blood is interconnection.

Human people are not the only ones with blood. Plant people have blood-like substances (“callose”) that gather together to heal a cut, pass nutrients throughout the body of the plant, and clear out toxins (Nosowitz, 2016). Blood works to communicate and monitor what is happening inside and outside of a body. This means that blood has a deep focus on relationship between beings and elements: carrying oxygen breathed in from the outside, closing a break in the skin, and helping to discern what can come inside the body.

These substances are, literally, relationship trackers and holders. Which is why the story of blood is a story of relationships. The story of blood as it has been written by the MIC is a story of separation, categorization, and a collective wound that creates more violence. It’s been the story of what happens when relationships become infused with destruction and disregard rather than the dignity of connection and care. How can we shift this story?

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