Otto Abeles was born in Brno (Bruenn), Moravia (now in the Czech Republic), where he was raised. In Brno Abeles was one of the organizers of Veritas, an organization of Jewish students, and among the founders of the Zionist movement in Bohemia and Moravia. He soon became part of Bertold Feiwel and Robert Strickers’ circle in Zionist activities.
After his studies at the Vienna University Abeles was employed as legal advisor to the Austrian Railways. His flair for writing led him to move into journalism. He was one of the editors of the Zionist newspaper Die Welt and the Jueddische Zeitung. He also wrote articles for the Yiddische National Zeitung and other newspapers. Together with Stricker he founded the Zionist daily newspaper the Wiener Morgenzeitung. In 1926, Abeles became emissary for Keren Hayesod and lectured throughout Western Europe. From 1930 he served as director of Keren Hayesod in Amsterdam. Among his major works are Die Genesung (1920) a book of poems, Besuch in Eretz Israel, a description of his first visit to Palestine (1926), and Zehn Juedinnen (1931), about famous Jewish women.
Abeles died of exhaustion in 1945, shortly after his liberation from the Nazi concentration camp at Bergen Belsen.