Immediately after the war, a large number of medical clinics were set up in Japan to treat wounded Japanese soldiers.
Of approximately 30,000 patients seen in these clinics, around 10,000 of them suffered from mental illnesses, such as “war neurosis.”
The Japanese government did their best to suppress any knowledge of said psychological trauma (indeed a 1938 Imperial Japanese Army (IJA) statement declared how Japanese soldiers did not suffer war neurosis unlike Western soldiers).
For the IJA, “war neurosis” was something that detracted from the “masculinity” of the IJA, and it was utilized and associated with “hysteria,” which was often used as a blanket diagnosis for women in the West.
After the war, virtually anything that was associated with the war and Japan’s defeat was essentially hushed up, including the fate of Japan’s veterans who essentially had to live with the knowledge of their defeat quietly.
This included these “war neurosis” victims.
These sufferers had many of the same conditions we would commonly associate with PTSD.
They would often hallucinate or dream of various war traumas, with at least some sufferers talking about killing children with their own hands or shooting down civilians or hearing the screams of women and children in their heads.
One sufferer reported that he had stabbed a Chinese man with his bayonet and felt that time had stopped ever since.
Even as late as 30 years after the war, medical clinics reported treating over a thousand veterans for mental health.
682 patients never left the mental health sanatoriums they entered at the end of the war.
The sufferers had higher than average unemployment and many reported having received no or little treatment for their condition.
Mental health issues from the war were considered shameful in Japan, so often times people covered up their condition as best they could or alternatively they were ostracized by their family and friends.
It was only with the sudden interest in the fate of WW2 veterans in the 90s and afterwards that this sort of information began coming to light.
Although most official records did not include many of these details (due to anything relating to Japanese atrocities not exactly being well-documented in official Japanese war documents) there was enough witness testimony from both those affected and the doctors that treated them to corroborate the story.