Rabbi Yitzchak Hadad was born in Algeria and is counted among the great sages of the island of Djerba in Tunisia. Having settled there, he extended his stay to benefit from the teaching of his masters, Rabbi Nissim Hayat and Rabbi Avraham Hacohen, who trained him both to issue halachic rulings and to teach Torah. The Jewish Encyclopedia, for its part, describes him as a pupil of Rabbi Tzemach Hacohen.

From his youth he adopted a practice previously unknown in Tunisia: having his chiddushim, along with the teachings he had received from his masters, printed so that they would be preserved and shared with his community. He was thus the first of the sages of Djerba to publish his writings.

Works: Karnei Re'em, on the commentaries of Rashi and Rabbi Eliyahu Mizrachi on the Torah; Zera Yitzchak, a collection of chiddushim and notes on the Midrashim (Livorno, 1765); and Toldot Yitzchak, printed in Livorno in 1761, described by different sources either as commentaries on the Talmud or as novellae on the Aggadah and Midrashim.

He had three sons, Rabbi Yaakov, Rabbi Shimon and Rabbi Avraham. The youngest, Rabbi Avraham, founded a synagogue that still bears his name, where he kept a room for his father to study and to settle community matters.

Rabbi Yitzchak Hadad passed away on 9 Adar 5515 (1755) in Djerba.