Well, it was around but inconsistently applied. Einstein famously got angry when his work on gravity waves in 1935 was sent out to review ("I sent my paper to be published, not to be reviewed!"), and Watson & Crick's 1953 paper was going to be sent out to review but their boss, Nobel Laureate Laurence Bragg, phoned up the editor of Nature and said they needed to get it published ASAP.
Forty years ago there was already this sentiment, as best as I can recall the quote: "It is well known that as the scale of the research grows, peer review becomes less effective."