Between 1900 and 1914 many so-called “insane re-migrants” (geisteskranke Rückwanderer) from America were admitted to the psychiatric institution in Hamburg-Friedrichsberg. These patients were mainly East European emigrants who had left Europe via Hamburg, had been classified insane and had been sent back by the US authorities. A total of 446 relevant medical files are available. This article concentrates on the years 1900 through 1903, and focuses on the issue of foreign language interpreting in psychiatric practice. Two cases — two multilingual Friedrichsberg patients who assumed the function of interpreters in each case of a foreign “insane re-migrant” — will be described in detail. The interpreters played a significant role in the reconstruction and documentation of the medical histories of their fellow patients. Conversations and interrogations carried out by them and recorded by their own hand have been passed down in the medical files of the patients they “examined”. The files of the multilingual patients themselves were also found in the archives. Thus, their activity as asylum interpreters can be viewed in the context of their own medical histories, i.e. their own mental condition.