Contemporaries described Abraham Lincoln's periods of profound sadness and even suicidal thoughts as "melancholy." Today, we know that America's 16th president was actually battling clinical depression.
The condition, coupled with anxiety attacks, ran in his family and plagued him from a very young age, when he was still simply a young lawyer in Illinois. As his law partner, William Henderson, once said, "His melancholy dripped from him as he walked."Wikimedia Commons
According to contemporary research reported by organizations like the International OCD Foundation and National Geographic, Serbian inventor Nikola Tesla suffered from severe obsessive-compulsive disorder throughout his adult life.
As National Geographic writes, "He loathed jewelry and round objects and wouldn't touch hair. He was obsessed with the number three and polished every dining implement he used to perfection, using 18 napkins."Wikimedia Commons
Vincent van Gogh
As the American Journal of Psychiatry writes, Dutch painter Vincent van Gogh "had an eccentric personality and unstable moods, suffered from recurrent psychotic episodes during the last 2 years of his extraordinary life, and committed suicide at the age of 37. Despite limited evidence, well over 150 physicians have ventured a perplexing variety of diagnoses of his illness."
Those diagnoses, according to the journal, include depression, bipolar disorder, epilepsy, but also schizophrenia, which may have run in his family. However, other writers and physicians have since disputed this diagnosis.Wikimedia Commons
Perhaps more than any other figure in history, Adolf Hitler both elicits infinite diagnoses of possible mental disorders and renders any definitive conclusions about said diagnoses all but impossible to attain. As elusive as definitive conclusions may be, that hasn't stopped a veritable subfield concerned with Hitler's possible psychopathology from springing up.
Dozens of physicians and writers who either knew Hitler personally or studied him posthumously have advanced possible diagnoses of everything from schizophrenia to narcissistic personality disorder to sadistic personality disorder to antisocial personality disorder to Asperger's syndrome.Wikimedia Commons
In 2015, several major news outlets gained access to a secret 2008 Pentagon study that claimed that Russian leader Vladimir Putin may have autism, specifically Asperger's syndrome.
A team of doctors studied Putin's movement patterns and defensive behavior in large social settings to ultimately conclude that his "neurological development was significantly interrupted in infancy" by some tragic event and that he now "carries a neurological abnormality."Wikimedia Commons
Wolfgang Amadeus Mozart
He created some of the most sophisticated music ever written, yet is also well-known for some of the most vulgar scatology you'll ever read. Indeed, many now know that the letters, biographies, and unofficial compositions of Austrian composer Wolfgang Amadeus Mozart are filled with references to feces, buttocks, and the like.
And what some medical journals have now suggested is that these vulgar preoccupations — along with his vocal and motor tics — indicate that Mozart had Tourette's syndrome.Wikimedia Commons
When Beat poet and novelist Jack Kerouac reported for duty in Rhode Island after joining the Navy in 1943, his superiors noticed his odd behavior and quickly transferred him from the training station to the Naval Hospital.
There, doctors noted that "neuropsychiatric examination disclosed auditory hallucinations, ideas of reference and suicide, and a rambling, grandiose, philosophical manner," diagnosed him with dementia praecox (schizophrenia), and discharged him on psychiatric grounds.Wikimedia Commons
While Soviet dictator Joseph Stalin numbers among the tyrannical world leaders that researchers have later tried to diagnose with clinical narcissism, he also appears to have exhibited paranoid personality disorder.
Both historians and medical journal writers have suggested that, perhaps stemming from the childhood abuse he received from his drunken father, Stalin developed a clinical paranoia that informed his more terroristic acts as dictator decades later.Wikimedia Commons
Many know that English scientist Charles Darwin sailed to the Galapagos Islands and elsewhere aboard the HMS Beagle in 1831, during which time he gathered evidence that would help him formulate the theory of evolution.
Few, however, know that after Darwin returned from that voyage, he very seldom left home and lived as a recluse for the rest of his life.
The reason, according to recent research published in the Journal of the American Medical Association? Darwin suffered from agoraphobia and panic disorder.
"Had it not been for this illness," suggests the research, "his theory of evolution might not have become the all-consuming passion that produced On the Origin of Species."Wikimedia Commons
Current scholarship published in medical journals and elsewhere suggests that Renaissance artist Michelangelo had both obsessive-compulsive disorder and high-functioning autism (namely Asperger's syndrome).
"The evidence," writes the Journal of Medical Biography, "relates to his single-minded work routine, unusual lifestyle, limited interests, poor social and communication skills, and issues of life control."Wikimedia Commons
Some say that it's all right there in his paintings, like The Scream (pictured). But that's certainly not the only evidence that Norwegian artist Edvard Munch suffered from clinical anxiety and hallucinations.
Understanding that his "condition was verging on madness," as he later wrote, Munch entered a therapeutic clinic, where he received eight months of treatment (including electrifications) in 1908.Wikimedia Commons
Scholars have long suggested that English writer Charles Dickens suffered from severe depression, perhaps even bipolar disorder, throughout his life.
In what is perhaps the most enduring diagnosis of a mental disorder among prominent historical figures, many have long believed that Roman emperor Julius Caesar suffered from epilepsy.
And while that may still be true — definitive diagnoses in cases from the BC era are of course difficult — new scholarship suggests that he may have actually suffered from small strokes instead, in addition to vertigo. Wikimedia Commons
It's easy to see how many could suspect that some of history's most powerful leaders were fueled by clinical narcissism. And when attempting to actually diagnose said leaders with narcissistic personality disorder (NPD), why not start with Napoleon?
Indeed, some current scholarship suggests that the notoriously megalomaniacal French conqueror likely had NPD.Wikimedia Commons
Ludwig van Beethoven
Contemporary reports in The New England Journal of Medicine and The British Journal of Psychiatry now suggest that German composer Ludwig van Beethoven suffered from bipolar disorder.
These journals even suggest that one can hear Beethoven's dramatic swings from suicidal depression to frenzied mania in the dramatic swings in dynamics and tempo in the man's music.Wikimedia Commons
British Prime Minister Winston Churchill referred to his recurring bouts with depression as his "black dog." But his physician, Lord Moran, took note of Churchill's depression — as well as his mania, suicidal thoughts, and sleeplessness — and made a more official diagnosis: bipolar disorder.Wikimedia Commons
An early 1980s CIA study cited by Bob Woodward's Veil claims that Libyan dictator Muammar el-Qaddafi had "borderline personality disorder."
It remains somewhat unclear, however, whether the CIA used that term in its clinical sense (a mental disorder characterized by unstable moods, behavior, and relationships) or more loosely to refer to someone who simply, as Woodward writes, "alternated between crazy and noncrazy behavior."Wikimedia Commons
Be it in biographies or medical journals, many writers have long stated that American author Ernest Hemingway suffered from clinical depression, perhaps coupled with bipolar disorder and even borderline and narcissistic personality traits.
Coupled with alcohol dependence and a traumatic brain injury, Hemingway frequently sank into long periods of depression before ultimately committing suicide at 61 in 1961.
While it's understandably difficult to diagnose a man who died in the 1720s, many contemporary writers and medical journals have suggested that English scientist Isaac Newton suffered from bipolar disorder.
Those who subscribe to this theory point to Newton's swings between periods of enraged mania (such as when he threatened to burn his parents house down with them inside it) and wallowing depression including delusions and hallucinations.Wikimedia Commons
English author Virginia Woolf's battles with severe depression and bipolar disorder are well documented in both biographic and medical literature from the The American Journal of Psychiatry and elsewhere.
According to the journal, Woolf "experienced mood swings from severe depression to manic excitement and episodes of psychosis," all of which landed her in an institution for a time and informed her bouts of suicidal thoughts.Wikimedia Commons
Scholars writing in The International Journal of Psychoanalysis and elsewhere have long suggested that Russian writer Leo Tolstoy dealt with clinical depression.
"After writing War and Peace," the journal reads, "his existence had been torn apart by a serious depression. This depression, which was melancholic in character, almost destroyed him and, once he had finished Anna Karenina, led him to want to renounce not only sexuality but also literary creation and material possessions."Wikimedia Commons
In 2009, researchers at Hungary's Semmelweis University published new findings about a relatively seldom-studied gene called neuregulin 1. To that point known almost solely as a gene that increased one's susceptibility to schizophrenia, neuregulin 1 belonged to the study of madness.
What the Semmelweis researchers did, however, was connect the gene not just to madness, but to genius as well.
Confirming Aristotle's immortal yet disputed quotation stating that "No great genius has existed without a strain of madness," the 2009 study found that neuregulin 1 informed brain development and neural communication in ways that increased both one's creativity and one's likelihood of developing any number of psychoses, including schizophrenia and bipolar disorder.
While this result provided a scientific underpinning for the link between genius and madness, it's safe to say that most of us already understood, at least implicitly, that that link was there.
Surely, most of us had noticed the frequency with which our favorite writers and artists sank into depression, suffered breakdowns, and committed suicide relative to the general population.
Indeed, as researchers at Sweden's Karolinska Institute found in 2014, people working in creative fields (dance, writing, photography, and so on) were significantly more likely to have — or at least have a family history of — mental issues like schizophrenia, bipolar disorder, and autism.
The Karolinska researchers found that writers, in particular, were 121 percent more likely to suffer from bipolar disorder compared to the general population, and nearly 50 percent more likely to commit suicide.
However, it's not only clinically depressed writers like Ernest Hemingway and Virginia Woolf who demonstrate the link between genius and madness; it's also political leaders, inventors, and scientists who have battled mental disorders that both tormented and fueled them.
And sometimes, the link between genius and madness is even apparent in other historical figures whose world-changing albeit loathsome qualities force us to stretch our very notion of "genius." These are the tyrants and conquerors, like Napoleon and Stalin — people who changed history immeasurably regardless of where we think they fall on the spectrum from good to evil.
From Stalin to Hemingway and beyond, discover some of the iconic historical figures who grappled with serious mental disorders in the gallery above.
Next, read up on 12 more historic figures who struggled with mental illness. Then, discover five of the world's most unusual mental disorders. Finally, read some of the most powerful Ernest Hemingway quotes ever.