Josef Jona Horovitz was rabbi to the Israelitische Religionsgesellschaft ("Religious Society of Israelites") from 1929 to 1938, succeeding Salomon Breuer. He was born in Hunsdorf, Czechoslovakia, and possessed great knowledge of the Talmud. In 1929 he was elected rabbi to the Israelitische Religionsgesellschaft, an office which had remained unfilled for three years. During this period the Society had been split by violent disagreement, with a minority trying to ensure the continuation of the Hirsch-Breuer dynasty and elect the son of Salomon Breuer, the previous incumbent, to the rabbinacy, and the majority faction preventing this.
In contrast to his predecessor, Horovitz was a relaxed, extrovert individual who strove to reconcile the conflicts between Jews. He remained in Frankfurt until the pogrom of November 1938. He regarded the persecutions as so dangerous that he suspended the commandment which forbids traveling on the Sabbath. This meant that strict Jews were able to use the railway on the Sabbath to flee to safety abroad. He was arrested and imprisoned by the police. Following his release, he emigrated to England at the end of November 1938 as a Czechoslovakian citizen. After spending some time in the USA, he settled in Israel at the start of the Sixties, and died there in 1970. He is buried in Jerusalem.