Otto Erich Hartleben (3 June 1864 – 11 February 1905) was a German poet and dramatist from Clausthal, known for his translation of Pierrot Lunaire.
Orphaned as a child, Hartleben was brought up by his grandfather in Hanover. Among his youthful acquaintances there were Karl Henckel, Arthur Gutheil and the future industrialist and politician Alfred Hugenberg and together they published a volume of poetry Quartett in 1886. After completing his schooling in Celle in 1886 he went to study law, first in Leipzig, where he got to know Hermann Conradi and Adolf Bartels, and later in Berlin. He studied for the civil service in Stolberg (Harz) and in Magdeburg. Giving up his legal studies, he returned to Berlin where he lived as a freelance writer, eventually moving to Munich in 1901. After the death of his grandfather in 1893, Hartleben inherited 80,000 marks and on 2 December married his lifelong companion, ex-waitress “little mop” Selma Hesse.
In 1900 he had a resounding success with his “officer’s tragedy” Rosenmontag (Carnival Monday) which deals with an ill-fated affair between a simple girl and a young officer from an old military family. He used the proceeds to purchase the Villa Halkyone in Salò on Lake Garda. Here he founded in 1903 the Halkyone Academy for the Pure Sciences, which included among its members Peter Behrens, Otto Julius Bierbaum, Franz Blei, Gerhart Hauptmann, Alfred Kubin, Emil Orlik and Ferdinand Pfohl, and which boasted just two rules: "§ 1. Membership of the Halkyone Academy confers neither duties nor rights. § 2. Everything else is governed by the spirit of the Halkyone community."