Some of the main causes of death prior to 1900 are mentioned, including disastrous epidemics of high mortality such as plague, smallpox and the so-called hunger epidemics. Also discussed are two chronic diseases remarkable for Iceland in old times, i.e., leprosy and hydatid disease.In the first third of the 20th century, infectious diseases still were the main cause of death in Iceland. The importance of tuberculosis in this connection is stressed. The very high infant mortality up to the beginning of this century is stressed. The changes in the main causes of death in the last decades are described and the growing influence of degenerative vascular diseases and cancer in that connection pointed out. Last, the remarkable fall in the infant mortality and increasing life expectancy from the beginning of this century with growing prosperity of the nation is stressed.