Modern cosmology began with the realization that there were solutions to Einstein's theory of gravity discovered by Friedmann and Lemaitre which when combined with the redshift distance relation of Hubble and others could be interpreted as showing that we live in an expanding universe. By 1930, the scientific establishment and many of the lay public believed this. It was then only elementary logic to argue that if time reversal was applied, the universe must originally have been so compact that we could talk of a beginning. Lemaitre tried to describe this state as the “Primeval Atom.” For a decade or so after the war, Gamow, Alpher and Herman and other leading physicists explored this dense configuration trying to make the chemical elements from protons and neutrons. They soon learned that this was not possible because of the absence of stable masses of five and eight, but they also realized that if such an early stage had occurred the universe would contain an expanding cloud of radiation which would preserve its black body form. Dicke and his colleagues in Princeton rediscovered this idea and decided to try and detect the radiation. Penzias and Wilson found such a radiation field, and COBE has demonstrated that it has a perfect black body form out to radio wavelengths. This history of the discovery together with the fact that the light elements D, He3 and He4 in about the right amounts can be made in a hot big bang has led to the widely held, but simplistic view, that the standard cosmology - the hot big bang - is correct.