Tiiiiny nitpick: overland camo is, well, land colored. Marine camo is ocean colored. Basically, whatever color would be below the hardware when an enemy viewed it is the theme you want. For instance, ocean camo overland? Ain't camouflage, now is it?
Yes, in "western" society Albert Hoffmann was the first person to see color. Among eg. Amazon tribes and First Nations folks in the US seeing color was more common, thanks to religious uses of hallucinogens.