Naturist movement in antique Greece was not needed, because naked human body was not considered as ugly or sinful. In middle ages naturism was not possible due to obscurantism and restrictions. Naturism appeared as a movement in Germany in 1903. It was called FreiKorperKultur or shorter FKK. In the beginning naturists claimed that naturism was not connected with sexuality, so it was not a "sin" :-). Some of naturist clubs had more rules then members. There are some so severe naturist clubs nowadays also, but fortunately, the number of them has been decreasing. The new generations of naturists are not interested in rules and ideology, they seeks for joy and freedom. They are people who enjoy bathing and sunbathing nude, recreating and gathering with other people. They do not want to join official naturist clubs and pay fees. They just go to a naturist camp or beach where nobody asks them about membership. Fortunately, there are more and more places like that. For naturists sexuality is not a taboo theme. They do not hide their interes for it and they admit sexuality takes a great part in their life, just like in life of other people. No doubts, naturists have more open minded and healthier relation toward sexuality. They have tolerance for all kind of sexual orientations. You can read more about it in this book.
However, the differences and conflicts between naturists and nudists have to be forgotten. It is important to spread our beliefs like respecting poeple of all ages, races, religions or sexual orientation; respecting privacy and property of other people, peacefulness and of course accepting our bodies as they are.