Color has been associated with thin films of materials for longer than we know, but, although the effect was known and observed, it was not fully understood until comparatively recently. It was the 19th Century before the interference effects in thin films that are responsible for their color, were properly recognized. Then the subjective, human response that is color, had to wait until the 20th Century before objective methods of defining it were accepted. Nowadays, there are many applications where the color of an optical coating is its most important attribute. This talk will survey some of the history of the struggle to understand and master the color of optical coatings. This is inextricably mingled with the history of color itself and so much of this account deals with the general problem of color.