The data of the "Little Ice Age" (1500-1850) in Croatia and those which applied to human health were especially emphasized were analyzed. They are some which stand out like: importance of the sort of soil and relief, the influence of cutting down of woods and cattle-breeding and especially the war which lasted for 250 years in the territory of Croatia. The important interactions between those parameters were defined. The important correlations were also defined between freezing and long winters as well as wet springs and summers which caused starvation, malnutrition and the increase of infant mortality and also epidemics with enormous psychological stress among people in that period. The result was witch-hunting and burning (which was also advocated in the other parts of Europe) and they sometimes reached the levels of madness. Considering that such events were unknown in the earlier periods (in such proportions) and that (even today) the influence of the slow virus is emphasized in connection to the etiology of schizophrenia so why should't it be supposed that the "Litlle Ace Age" could be the cause of the larger prevalence of schizophrenia in the teritory of Croatia.