R. Zvi Pesah Frank (1873–1960), chief rabbi of Jerusalem and halakhic authority, was born in Kovno, Lithuania. His father, R. Judah Leib, was one of the leaders of the "Haderah" society in Kovno which founded the village of Haderah in Erez Israel. He studied under R. Eliezer Gordon at Telz and under R. Isaac Rabinowitz at Slobodka. He attended the musar discourses of R. Israel Lipkin of Salant. In 1893 he proceeded to Jerusalem where he continued his studies at the yeshivot of Ez Hayyim and Torat Hayyim. He acquired an outstanding reputation, combining a profound knowledge of the Talmud with sound common sense. Despite his youth, he was encouraged by R. Samuel Salant, the rabbi of Jerusalem, who consulted with him in his halakhic decisions. In 1895 he married Gitah-Malkah, granddaughter of R. Hayyim Jacob Spira, head of the Jerusalem bet din. Subsequently he taught at a number of Jerusalem yeshivot. In 1902 he moved to Jaffa in order to be able to devote himself entirely to study. R. A. I. Kook had already taken up his appointment there, and later he and R. Frank associated in the efforts to establish the rabbinate of Israel.

In 1907 R. Frank was appointed by R. Salant and the scholars of Jerusalem as a member of the Bet Din Gadol in the Hurvah synagogue. Although he was its youngest member, the burden of the bet din, and the religious affairs of the city fell mainly upon his shoulders. He conducted single-handedly the spiritual administration of the city in the difficult days of World War I. The Turks tried to send him into exile in Egypt, but he hid in an attic from where he directed the rabbinical affairs of the city until the entry of the British (December 1917). The rabbinate was in a perilous state and Frank made strenuous efforts to raise its status, both materially and spiritually. He understood the importance of founding a central rabbinical organization, and immediately after the British occupation, took steps to found "The Council of Rabbis of Jerusalem." This organization, however, was shortlived. Later, however, he established the "Rabbinate Office," which became the nucleus of the chief rabbinate of Israel, and on his suggestion R. A. I. Kook was invited to become chief rabbi of Palestine in 1921. In the violent controversy which resulted, fomented by the extreme religious section which saw no halakhic precedent for such an appointment, R. Frank brought proof to bear. In 1936 he was elected chief rabbi of Jerusalem. In consequence of his preeminence as a halakhist, the appointment was accepted by all parties, including those who opposed him on political grounds.

R. Isur Zalman Meltzer (1870–1953), talmudic scholar and yeshivah head was born in Lithuania. He studied in Volozhin under R. Hayyim Soloveichik and R. Naphtali Zevi Judah Berlin, and later under the Hafez Hayyim in Radin. All of these exercised a profound influence upon him, R. Soleveichik by his talmudic methodology, R. Berlin by his love for Erez Israel, and the Hafez Hayyim by his humility and his ethical approach. In 1892 he married Beila Hinda, daughter of R. Faivel Frank of Ilukste. His wife possessed considerable scholarly abilities and throughout his life assisted him in transcribing his works and in arranging them for publication. In 1894 he was appointed by R. Nathan Zevi Finkel one of the principals of the Slobodka yeshivah and in 1897 the head of a yeshivah for advanced students in Slutsk, where Jacob David Willowski was the rabbi. Hundreds of students flocked to the yeshivah, and when R. Willowski emigrated to Erez Israel in 1903 R. Meltzer succeeded him as rabbi of Slutsk. After the Bolshevik Revolution in 1917 the yeshivah moved to Kletsk in Poland. R. Meltzer, however, refused to leave his community in Slutsk, despite his suffering at the hands of the Bolsheviks, including imprisonment for teaching Torah. In 1923 he left Russia for Kletsk and in the same year participated in the founding conference of the Agudat Israel in Vienna, at which he was elected to the Mo'ezet Gedolei ha-Torah.

In 1925 he became head of the Ez Hayyim Yeshivah in Jerusalem. In Erez Israel, he devoted himself almost entirely to the dissemination of Torah and the strengthening of yeshivot. In 1935 his first work appeared, Even ha-Ezel on the Mishneh Torah of Maimonides which is regarded as a fundamental work of its kind. Seven volumes appeared during his lifetime, the other posthumously. He also edited and wrote commentary to the novellae of Nahmanides (1928/29).