Before all these dancers gained renown, Isadora Duncan had made modern dance virtually synonymous in popular consciousness with barefoot performance, and in 1903 she even went so far as to appear nude in a performance at the Kroll Opera in Berlin. Barefoot dancing may have signified the modernity of a body liberated from external (social) constraints (for which clothing is the most obvious sign), but efforts to extend nudity in performance beyond bare feet or beyond the solo performer always seemed to produce an enormous, quite unliberating anxiety. Barefoot dancing introduced a logic of signification that teased the spectator with a promise of liberation, which the dance world then hesitated to fulfill. Perhaps for this reason, the grotesque dancer Valeska Gert, who apparently never danced nude, asserted that "one should dance barefoot only when naked or simply covered with a shirt" (VP 13–16). Moreover, because all the early nude dancers were women, the European public seemed to regard nude dancing as a mode of erotic performance capable of sexually exciting its spectators.
Occasionally, German courts had to determine the legality of some of these dances (OG 49–73).
But it was clear even before the war that the legal ambiguity of nude dances did not stem entirely from a perceived threat to the female body posed by the male gaze, for audiences of nude dancing were as much female as male. Moreover, it became obvious during the 1920s that female nude dancing was inspiring many women to participate in modern dance culture. The degree to which nude dancing transgressed moral norms depended on the relation, in performance, between nudity and the signification of erotic desire. This relation apparently achieved transgressive power when a nude dance included both male and female bodies (with either gender dancing nude), for we encounter great difficulty in finding manifestations of such combinations of bodies. However, male interest in nude dancing did not confine itself to spectatorship. By 1910 Emile Jaques-Dalcroze had incorporated nudity into his ambitious program for the liberation of European bodies through systematic study of bodily movements and musical rhythms. "Nudity," he remarked,
provides not only a medium of control indispensable for purposes of physical expression, but is in addition an aesthetic element inducing the respect for the body that animated the great Greek philosophers. In proportion as the idea of sex subsides in the fervour of the artist, and in the passion for complete absorption in beauty and truth, so our bodies take on new life, and we feel lack of respect for nudity to be a sin against the spirit (Jaques-Dalcroze, 207; Appia, Oeuvre Complètes, III 14).
Dalcroze hoped that as erotic interest in nude movement waned, rhythmic gymnastics would gain wider support from the state and the public. An implication of his argument was that a linking of nudity to erotic signification produced a profound anxiety toward the body, impeding the hygienic or therapeutic, rather than aesthetic, significance of movement studies. But after the war, Dalcroze's linking of nudity to an idealized classical antiquity seemed an inadequate sign of modernity; indeed, nudity was modern to the extent that it avoided classical models. Of greater significance by far in shaping German attitudes toward the relation between nudity and dance was the strange and complex world of Nacktkultur (free body movement). However, by 1930 Nacktkultur had not succeeded at all in changing the conditions under which nude dance had been possible in 1920. Getting men involved with nudism was hardly a problem, but getting them to perform modern dances was, and getting them to perform nude dances was practically impossible.