Race Suicide:
"What is fundamentally infinitely more important than any other question in this country—that is, the question of race suicide…

The man or woman who deliberately avoids marriage, and has a heart so cold as to know no passion and a brain so shallow and selfish as to dislike having children, is in effect a criminal against the race, and should be an object of contemptuous abhorrence by all healthy people.

If the men of the nation are not anxious to work in many different ways, with all their might and strength, and ready and able to fight at need, and anxious to be fathers of families, and if the women do not recognize that the greatest thing for any woman is to be a good wife and mother, why, that nation has cause to be alarmed about its future."
—US President Theodore Roosevelt, 1902

Race Suicide was a term coined in 1900 by eugenicist/ sociologist Edward A. Ross; which suggested a differential birth rate between native-born and immigrant women, or more generally between the "fit/ best" (white, wealthy, educated), and the "unfit/ undesirable" (poor, uneducated, criminals, diseased, mental and physical "defectives," and ethnic, racial, and religious minorities), such that the "fit" group would ultimately dwindle to the point of extinction.

Belief in Race Suicide is an element of Nordicism, anti-East Asian discourse (Yellow Peril) and modern White nationalism.

W. Stewart Wallace, the author of The Canadian Immigration Policy, claimed in 1906 that "immigrants did not increase a nation's population but merely replaced it".