Eugen D. Relgis (backward reading of Eisig D. Sigler; first name also Eugenio, Eugène or Eugene, last name also Siegler or Siegler Watchel; (22 March 1895 – 24 May 1987) was a Romanian writer, pacifist philosopher and anarchist militant, known as a theorist of humanitarianism. His internationalist dogma, with distinct echoes from Judaism and Jewish ethics, was first shaped during World War I, when Relgis was a conscientious objector. Infused with anarcho-pacifism and socialism, it provided Relgis with an international profile, and earned him the support of pacifists such as Romain Rolland, Stefan Zweig and Albert Einstein. Another, more controversial, aspect of Relgis' philosophy was his support for eugenics, which centered on the compulsory sterilization of "degenerates". The latter proposal was voiced by several of Relgis' essays and sociological tracts.