A brief history of child and adolescent psychiatry is traced, from old ages to modern times. The first area of interest of child and adolescent psychiatry, particularly in Europe, has been mental retardation, while the second area of interest and research, alive especially in the United States since the beginning of the XX century, was juvenile delinquency. Subsequently, the origins of child and adolescent psychiatry in Italy are examined, especially with the contributions of the three pioneers Sante De Sanctis, Giuseppe F. Montesano, and Maria Montessori (This is the first part of three parts that are published in three consecutive issues of this Journal: nos. 125, 126, and 127 of year 2014).
Keywords: Child and adolescent psychiatry, history, mental retardation, juvenile delinquency, Maria Montessori