Mental illness, as we know it was seldom acknowledged in the 1940's unless it became unmanageable. It was a hidden disease. Psychoanalysis ca. Freud and Jung were popular as were frontal lobectomies...
The Irish was the largest immigrant group in the 1800s and they were generally treated poorly. Later immigrant groups were treated the same way as the Irish immigrants of the early 1800s.
They were sent to various mental hospitals for treatment of their mental illnesses and if that was not successful were grieviously undermined by the social ineptitude of the lower socio-economic...