[5][3] In 1926, she was invited by Suzanne Lenglen to play international tournaments at the French Riviera at a time German players were still banned from international tournaments as a consequence of World War I. Neppach traveled to France despite a warning from the German tennis federation and played matches against Lenglen as well as U.S. legend Helen Wills.

[8] During the following years, Neppach's and Ilse Friedleben's place at the top of German women's tennis was taken by younger and more successful players like Cilly Aussem and Hilde Krahwinkel.

[2][9] On 11 April 1933, ten weeks after the Nazi Regime had seized power in Germany on 30 January, Neppach, who was Jewish, quit her membership at Tennis Borussia.

[1] On the night of 7/8 May 1933, Neppach, faced with increasing discrimination and persecution of Jewish people in Germany and her isolation from tennis in particular, took her life in her flat at Berlin using Barbital and town gas.

"It is impossible to publish a complete list of the suicides brought about by Nazi brutality," wrote the Hebrew Standard of Australasia in mentioning her death.