On a note tangentially related to Deathwatch, in browsing through the second edition of the Horus Heresy forgeworld books the other day, I got to thinking about how many of the Primarchs display some traits associated with the symptoms of various mental illnesses.
I'm not in any way a mental health professional, so I don't really have any specialist knowledge here other than what I read online, but it is quite fun to engage in a bit of retrospective diagnosis for each of the Primarchs as if they were historical figures. This sort of activity has a long and ignoble history, with various armchair historians constantly arguing over whether George III really had porphyria, or whether Napoleon was poisoned by the arsenic in the wallpaper in his villa on Saint Helena.
Obviously the Primarchs are fictional characters, and thus any attempt at using modern diagnostic methods is therefore inherently flawed from the start. Furthermore, they are, in universe, genetically engineered super beings, with hidden functions coded into their very DNA by the Emperor. Plus, there are always going to be certain issues in dealing with certain types of apparent mental illness with the Primarchs where the symptoms relate to warp influence. Does Lorgar hear voices because he's schizophrenic, or because he's actually hearing Gods speak to him? In universe, the latter is true: modern diagnostic criteria don't take account of the existence of fictional gods as being the cause of symptoms of mental illness. So to a degree, this is a pointless exercise.
However, pointless exercises are often fun, in my experience!
So here we go, in no particular order:
Horus - psychopathy, Oppositional defiant disorder
Mortarion - depression, post traumatic stress disorder, Oppositional defiant disorder, Post-traumatic embitterment disorder
Fulgrim - Narcissistic personality disorder, obsessive compulsive personality disorder, perfectionism, impulse control disorder
Ferrus Manus - Body Dismorphic Disorder
Night Haunter/Conrad Curze - antisocial personality disorder, psychopathy, sociopathy, schizophrenia, nightmare disorder, impulse control disorder, Schizoid personality disorder
Lorgar - Borderline personality Disorder, temporal lobe epilepsy
Perturabo - Asperger's syndrome, Paranoid personality disorder, Schizoid personality disorder
Roboute Gulliman - obsessive compulsive personality disorder (highly debatable)
Lion 'El Johnson - social anxiety disorder, Paranoid personality disorder
Angron - impulse control disorder, post traumatic stress disorder, pain disorder, Intermittent explosive disorder, Post-traumatic embitterment disorder
Rogal Dorn - Creutzman Belling Syndrome, Asperger's syndrome
There's a few of the Primarchs, anyway. I've left out Magnus, Corax and Jaghati Khan because I don't really have enough of a handle on their personalities yet.
Vulkan doesn't strike me as having signs of any mental illness prior to Isstvan, though arguably intense post traumatic stress disorder is a possibility after his treatment at the hands of Konrad Curze.
Alpharius/Omegon also seem to be perfectly rational, as of "Legion" anyway.
Sanguinius is a hard one to nail down. Older canon had the black rage as a feature of the Blood Angels Chapter which was caused by his death, but this appears to have been retconned by the Horus Heresy novels to make it a pre-existing condition. The Black rage doesn't really fit any of the diagnostic criteria for mental illness - it's apparently more like a physical illness, or, in universe, arguably a psychic one. Certainly it appears to cause symptoms similar to intermittent explosive disorder, but in fact the effects are a bit more like a hyper-aggressive form of rabies.
Anyway, that's the fruit of my musings on the topic. Any thoughts anyone? Are any of my diagnoses unsustainable/wrong, in your view?