Descriptions of children with symptoms similar to contemporary concepts of mania date back to the 18th century. In 1898, a detailed psychiatric case history was published about a 13-year-old that met Jean-Pierre Falret and Jules Baillarger's criteria for folie circulaire, which is congruent to the modern conception of bipolar I disorder.[19] In Emil Kraepelin's descriptions of BD in the 1920s, which he called "manic depressive insanity", he noted the rare possibility that it could occur in children.