Etiology of croupous pneumonia remaining a challenging problem has a long history of investigations. The term croupous pneumonia is traditionally used in this country to describe the form of the disease characterized by hyperergic inflammation and specific clinical/laboratory parameters. A valuable contribution to the study of this condition was made by S.P. Botkin. This paper deals with evolution of the views of epidemiology, etiology, pathomorphology, and methods of therapy of croupous pneumonia since Botkin's time to these days.