Throughout history, people with mental illnesses have indeed been persecuted, marginalized, and discriminated against—both through institutional policies and societal attitudes:

In the Middle Ages and early modern period, mentally ill individuals, especially women, were sometimes persecuted as witches or considered possessed.

From the 16th century onward, people with mental illness were often confined in asylums, frequently under inhumane conditions. These institutions sometimes acted more as punitive prisons than places of care, with patients often chained, abused, or put on public display.

During the Nazi regime, persecution escalated into the systematic killing and sterilization of individuals with mental illnesses as part of programs aimed at eradicating those deemed "unfit"—amounting to what some historians refer to as psychiatric genocide.

In many societies, racist psychiatric theories were also used to justify the mistreatment and segregation of certain groups. For instance, in 19th-century America, doctors invented so-called "mental illnesses" to rationalize the enslavement and oppression of Black people, leading to separate and inferior facilities for African Americans who were mentally ill.

In the present day, while explicit legal persecution is less common in many countries, strong discrimination, stigma, and exclusion persist:

People with mental illness continue to face barriers in employment, housing, and healthcare, and are at greater risk of homelessness, incarceration, and premature death.

Stigmatization often deters individuals from seeking treatment and can worsen their conditions.

In some political regimes, psychiatric diagnoses have been misused to silence dissent or incarcerate undesirables, as in the Soviet Union or contemporary reports from China.

These patterns show that, both historically and presently, individuals with mental health conditions have been—and in many places continue to be—subject to persecution, discrimination, and rights violations.

Non-human life—especially animals—has historically been, and continues to be, persecuted and mistreated by humans.

Historically:

Animals were often subjected to extreme cruelty, with widespread practices such as bear-baiting, dog fighting, and cockfighting being common forms of entertainment in many societies up to the 19th century.

Prior to the 19th century, there were few legal protections for animals. In some cases, animals were even subjected to formal trials and punishments, as seen in medieval Europe where animals could be prosecuted and executed for supposed crimes.

The exploitation extended beyond mere entertainment—animals were used for labor, food, science, and sometimes blamed or punished for disease outbreaks or crop damage.

Shifts towards protection began in the 19th century with the introduction of the first animal welfare legislation, such as the 1822 Cruel Treatment of Cattle Act in the UK (“Martin’s Act”), followed by the founding of societies for the prevention of cruelty to animals.

Present day:

Despite modern animal welfare laws in some countries, animals continue to face persecution in the form of factory farming, wildlife trafficking, poaching, habitat destruction, and inhumane treatment in entertainment and experimentation.

Legal standards and enforcement vary widely, and there remain many regions where cruelty to animals is common and legislation is weak or absent.

These patterns demonstrate that non-human life—especially animals—has suffered systematic mistreatment throughout history and across cultures, and still faces significant persecution and inadequate protection globally today.

There are some notable links between the persecution of people with mental illnesses and the persecution of non-human life, particularly animals, in both historical views and social contexts:

Historically, people with mental illnesses were often likened to animals, viewed through the lens of "animalism." This meant they were considered irrational, unable to control themselves, capable of violence without provocation, and lacking sensitivity to pain or discomfort—similar to animals. This dehumanizing comparison justified harsh treatment and confinement, often under brutal conditions akin to how animals were treated.

The inhumane conditions in institutions for the mentally ill historically mirrored the harsh treatment animals received. Mentally ill patients were often chained, confined in filth, and exhibited for public spectacle, similar to how animals were confined and exploited for entertainment or labor.

Both groups—people with mental illnesses and non-human animals—have been subject to social stigma, marginalization, and institutional control rooted in notions of otherness and inferiority.

Overall, the persecution of people with mental illness and non-human life has had overlapping justifications and social mechanisms historically, grounded in dehumanization and othering, which facilitated discriminatory and cruel treatment toward both.

Perplexity

Here is a bibliography of relevant academic and scholarly works that support the point that persecution of people with mental illnesses and non-human life has overlapped historically, especially through mechanisms of dehumanization and othering:

• Haslam, N. (2006). “Dehumanization: An Integrative Review.” Personality and Social Psychology Review, 10(3), 252–264.
  (Widely cited for the concept of animalistic dehumanization and its function in justifying cruel treatment of marginalized human groups).

• Smith, D.L. (2011). Less Than Human: Why We Demean, Enslave, and Exterminate Others.
  (Discusses animalistic dehumanization as a propaganda and social strategy for marginalizing humans and drawing boundaries between “human” and “non-human”).

• Wren, C.L. et al. “The Medicalization of Nonhuman Animal Rights: Frame Contestation and the Exploitation of Disability.”
  (Analyzes how ableist narratives and dehumanization overlap in the rhetoric about both mental illness and animal rights movements).

• Bruneau, E., Kteily, N. (2017). “The enemy as animal: Symmetric dehumanization during asymmetric conflict among Israelis and Palestinians.” Nature Human Behaviour, 1(7), 0143.
  (Explores animalistic metaphors and dehumanization as a means of justifying the exclusion and mistreatment of outgroups).

• Hodson, G. (2023). “An integrated psychology of (animalistic) dehumanization and human–animal relations.” Current Opinion in Psychology, 101044.
  (Examines how animalistic dehumanization operates for both human and non-human victims).

• Heatherton, T.F., Kleck, R.E., Hebl, M.R., Hull, J.G. (Eds.). (2000). The Social Psychology of Stigma. Guilford Press.
  (Analyzes the mechanisms of stigma, prejudice, and the “single animal” model of marginalization, encompassing mental health and animality).

• Nehari, R. (2023). "The Overlapping of Animal and Human Rights." Journal of Legal Research and Juridical Science, 152.
  (Discusses intersectionality of systemic discrimination against both non-human animals and marginalized people, including those deemed ‘mentally ill’).

• Dovidio, J. F., Glick, P., & Rudman, L. A. (Eds.). (2005). On the Nature of Prejudice: Fifty Years after Allport. Blackwell Publishing.
  (Addresses mechanisms of stigma, prejudice, and othering, including animalization and dehumanization).

• Markowitz, D.M., Slovic, P. (2020). “Social, psychological, and demographic characteristics of dehumanization.” PNAS, 117(18): 9787–9792.
  (Shows the role of dehumanization in both historical and contemporary exclusion and violence).

Perplexity