Gatefold albums

[greenfire]

Just wondered if anyone knew when the gatefold albums were first introduced. Did it go back to the 1950s? I never owned any Fleetwood Mac in record format but it would have been nice to collect them. I never knew Penguin was originally gatefold record and to see the photo of the band in color was great. That is one of my favorite pictures of the band and to see it in color was impressive. Were any of the other Fleetwood Mac albums between 1967 and 1975 also gatefolds?