In 1900 Hungary was a regional power in Europe with imperial pretensions; by 1919 it was reduced to the status of a small Central European country, crippled by profound territorial, social and national transformations. This book chronicles the development of eugenic thinking in early twentieth-century Hungary, examining how eugenics was an integral part of this dynamic historical transformation. It served as a vehicle for transmitting social and biological messages that transcended the differences between political parties and opposing ideological world views. Hungarian eugenicists not only engaged in the same speculative debates concerning heredity and evolution as their counterparts did elsewhere in Europe and the USA, they also conjured up a national interpretation of the application of eugenics to society, one which aimed at solving long-standing social, economic and medical problems specific to Hungarian society.