Forty lost years of Coherent States

In search to satisfy the correspondence principle Schr\"odinger in 1926 introduced the minimum uncertainty state. Almost forty years later in 1963 Glauber put these states to use in what now know as quantum theory of optics. He also gave them the name we know them by, coherent states. And soon after Sudarshan completed Glauber's unfinished work in achieving the theory of quantum optics. Crucial mathematical work was done in these forty years to able Glauber to consider these states. I will discuss why Glauber was attracted to these states. I will talk about what it was that Schr\"odinger was after, and why they were forgotten for almost forty years.