Archduke Joseph of Austria mentioned his "only daughter" Aglaya. However the real Joseph Karl Ludwig of Austria didn't have a daughter with that name. In the 1890s he had four daughters, two of them, Maria and Margarethe, were already adults and his other two, Clothilde and Elisabeth, were children.
In court the supportive doctor mentioned that if medicine wouldn't develop they would still work like Dr. Eisenbarth 300 years ago. The surgeon Johann Andreas Eisenbarth lived in 1663-1727 which would be around 200 years ago before the plot's setting.