This paper focuses on the creation of the criminal insane asylum in Italy between unification in 1861 and World War I. The establishment of criminal insane asylums was a triumph of the positivist criminology of Cesare Lombroso, who advocated for an institution to intern insane criminals in his classic work, Criminal Man (1876). As a context for the analysis of the birth of the criminal insane asylum in Italy, this essay also outlines the history of the insanity plea in Italian criminal law and the young discipline of psychiatry during the fifty years after Italian unification.