Post-World War II baby boom

As is often the case with a large war, the elation of victory and large numbers of males returning to their country triggered a baby boom after the end of World War II in many countries around the globe, notably those of Europe, Asia, North America, and Australasia.

In the United States, demographers have put the generation's birth years at 1946 to 1964, despite the fact that the U.S. birthrate (per 1,000 population) actually began to decline after 1957. William Strauss and Neil Howe, in their book Generations, include those conceived by soldiers on leave during the war, putting the generation's birth years at 1943 to 1960. (Strauss and Howe base their years on peer personality, not parental fecundity, so their years may not coincide with the actual "boom" demographically.)

The key biological factor is that a woman is fertile only into her mid-forties, and while austerity and restraint were the norms during the stress of the war years in the lives of the various Rosie the Riveters, when the men came home many of those jobs left and marriage became again a cultural and career norm for most women — and one result was babies, which boom continued in the economic glow of the fifties, but dampened its rate as the recession of 1958 sloughed into the following recovery, but petered out as the biological capacity of the boomer parents took their natural course. Simple mathematics governs, a woman married in her mid-to-late twenties after the war ended in August 1945 was infertile twenty-or-so years later. Finer distinctions are statistical, although there is merit in the cultural view of Strauss and Howe, based in the cultural commonalities experienced by the boomers as they have defined them.

In Canada, the baby boom is usually defined as the generation born from 1947 to 1966—Canadian soldiers were repatriated later than American servicemen, and Canada's birthrate did not start to rise until 1947, and most Canadian demographers prefer to use the later date of 1966 as the boom's end in that country. The United Kingdom experienced a second baby boom during the 1960s, with a peak in births in 1964 and a third (smaller) one in the late 1980s.

The Baby Boom was brought to the public's attention in 1960, with the publication of Landon Y. Jones' Great Expectations: America and the Baby Boom Generation. That there was a boom is not denied. Live births in the United States surged from 222,721 in January 1946 to 233,452 that May. In October, 339,499 babies were born. By the end of the decade, about 32 million babies had been born, compared with 24 million in the lean 1930s. In 1954, annual births first topped four million and did not drop below that figure until 1965, when four out of ten Americans were under the age of twenty.

It is jokingly said that, whatever year they were born, boomers were coming of age at the same time across the world; so that Britain was undergoing Beatlemania while people in the United States were driving over to Woodstock, organizing against the Vietnam War, or fighting and dying in the same war; boomers in Italy were dressing in mod clothes and "buying the world a Coke"; boomers in India were seeking new philosophical discoveries; American boomers in Canada had just found a new home after escaping the draft south of the border; Canadian Boomers were organizing support for Pierre Trudeau; and boomers in Mexico were discovering new hallucinogenic drugs and rediscovering old ones. It is precisely these experiences why many believe that trailing boomers (those born in the 1960s) belong to another cohort, as events that defined their coming of age have nothing in common with leading or core boomers (which Daniel Yankelovich and other demographers made perfectly clear).

Although the term "boomer" has fallen into global use, the generation is also known in Europe as the Generation of 1968. The term is derived from a historically significant rise in the birthrate following the Second World War. Several factors have been credited with this rise, among them a general sense of relief at the war's end, and the resurgent economic conditions of the period.