Zvi Yehuda Kook was born in 1891 in Zaumel in the Kovno Governorate of the Russian Empire (now Žeimelis in Northern Lithuania), where his father served as rabbi.
His mother was his father's second wife, Reiza Rivka, the niece of Eliyahu David Rabinowitz-Teomim, Chief Rabbi of Jerusalem together with Shmuel Salant.
Kook was named after his maternal grandfather, Rabbi Zvi Yehuda Rabinowitz-Teomim.

In 1896, his father, with his entire family, moved to Bauska, Latvia, to serve as rabbi there.
There Zvi Yehuda Kook studied Talmud under the guidance of Rabbi Reuven Gotfreud, the son-in-law of Rabbi Yoel Moshe Salomon, the founder of Petakh Tiqva.
Later, he studied under R. Moshe Zeidel and Benjamin Levin.
His principal teacher, however, remained his father throughout his life.
His father also hired a private tutor to teach him Russian.

In 1904, at age 13, he moved to Jaffa, when his father was appointed Chief Rabbi of the city, then part of Ottoman-controlled Palestine.
Like his father, he would celebrate on each year the date of his ascent to Land of Israel, on the 28th day of Iyyar.

In 1906, Zvi Yehuda Kook went to study at one of the most prominent yeshivas in Jerusalem at that time, Torat Chaim, in the future building of Ateret Cohanim.
There, he became close to the Rosh Yeshiva, Rabbi Zerakh Epstein, despite being relatively young (around 15).

His studies there, however, did not last long.
He soon returned to Jaffa, where he assisted his father in an attempt establish a yeshiva in Jaffa.
During this time, he began his close relationship with Rabbi Yaakov Moshe Charlap, a disciple of his father and future dean of the Mercaz HaRav yeshiva, and assisted Charlap in publishing Tzvi laTzadik.

In 1910, at age 19, he assisted his father in publishing Shabbat Haaretz on the sale permit for the Sabbatical year, even writing some of the Halachic preface.

Seeing he lacked time to truly study Torah like most people his age, he decided to remove himself from public activity for some time.
First, he went to Porat Yoseph, the leading Sephardic yeshiva of Jerusalem.
Then, he left to Halberstadt, Germany, and studied there in the local yeshiva.
He also attended lectures at the local university.
In addition to his own studies, Kook taught Talmud, Halacha, and Bible to young men in the area.

With the outbreak of World War I in 1914, he was arrested as a citizen of the Russian Empire, the enemy country.
After several weeks under difficult conditions in a detention camp in Hamburg, he was released and allowed to return to Halberstadt, where he needed to report once every two days in the local office.
Only the following year, at the end of 1915, was he granted permission to leave Germany and join his father in Switzerland, where he was stuck due to the war.
There he learned with his father, until his father left in 1916 to fill a rabbinic position in London.

In 1920, he returned to Palestine (then under the British Mandate) and began teaching at Netzakh Israel school.
A year later, he went to Europe to promote his father's new movement, "Degel Yerushalayim", among the leading rabbis of Europe.

In 1922, he married Chava Leah Hutner in Warsaw.
Chava Leah died childless in 1944, and Rabbi Tzvi Yehuda remained a widower until his death nearly 40 years later.
From 1923, he served as the administrative director of the Mercaz HaRav yeshiva.
After Rabbi Charlap died in 1952, he became Rosh Yeshiva until his own death.
After the Six-Day War in 1967, he induced the Israeli government to approve the building of settlements in the West Bank and Gaza, and sent his students to that mission.
He tried to strengthen the Chief Rabbinate, which he saw as the precursor of the future Sanhedrin.

He passed away in Jerusalem on Purim of 1982, and was buried in the Mount of Olives Jewish Cemetery.
Zvi Yehuda Kook was born in 1891 in Zaumel in the Kovno Governorate of the Russian Empire (now Žeimelis in Northern Lithuania), where his father served as rabbi. His mother was his father's second wife, Reiza Rivka, the niece of Eliyahu David Rabinowitz-Teomim, Chief Rabbi of Jerusalem together with Shmuel Salant. Kook was named after his maternal grandfather, Rabbi Zvi Yehuda Rabinowitz-Teomim.
In 1896, his father, with his entire family, moved to Bauska, Latvia, to serve as rabbi there. There Zvi Yehuda Kook studied Talmud under the guidance of Rabbi Reuven Gotfreud, the son-in-law of Rabbi Yoel Moshe Salomon, the founder of Petakh Tiqva. Later, he studied under R. Moshe Zeidel and Benjamin Levin. His principal teacher, however, remained his father throughout his life. His father also hired a private tutor to teach him Russian.
In 1904, at age 13, he moved to Jaffa, when his father was appointed Chief Rabbi of the city, then part of Ottoman-controlled Palestine. Like his father, he would celebrate on each year the date of his ascent to Land of Israel, on the 28th day of Iyyar.
In 1906, Zvi Yehuda Kook went to study at one of the most prominent yeshivas in Jerusalem at that time, Torat Chaim, in the future building of Ateret Cohanim. There, he became close to the Rosh Yeshiva, Rabbi Zerakh Epstein, despite being relatively young (around 15).
His studies there, however, did not last long. He soon returned to Jaffa, where he assisted his father in an attempt establish a yeshiva in Jaffa. During this time, he began his close relationship with Rabbi Yaakov Moshe Charlap, a disciple of his father and future dean of the Mercaz HaRav yeshiva, and assisted Charlap in publishing Tzvi laTzadik.
In 1910, at age 19, he assisted his father in publishing Shabbat Haaretz on the sale permit for the Sabbatical year, even writing some of the Halachic preface.
Seeing he lacked time to truly study Torah like most people his age, he decided to remove himself from public activity for some time. First, he went to Porat Yoseph, the leading Sephardic yeshiva of Jerusalem. Then, he left to Halberstadt, Germany, and studied there in the local yeshiva. He also attended lectures at the local university. In addition to his own studies, Kook taught Talmud, Halacha, and Bible to young men in the area.
With the outbreak of World War I in 1914, he was arrested as a citizen of the Russian Empire, the enemy country. After several weeks under difficult conditions in a detention camp in Hamburg, he was released and allowed to return to Halberstadt, where he needed to report once every two days in the local office. Only the following year, at the end of 1915, was he granted permission to leave Germany and join his father in Switzerland, where he was stuck due to the war. There he learned with his father, until his father left in 1916 to fill a rabbinic position in London.
In 1920, he returned to Palestine (then under the British Mandate) and began teaching at Netzakh Israel school. A year later, he went to Europe to promote his father's new movement, "Degel Yerushalayim", among the leading rabbis of Europe.
In 1922, he married Chava Leah Hutner in Warsaw. Chava Leah died childless in 1944, and Rabbi Tzvi Yehuda remained a widower until his death nearly 40 years later. From 1923, he served as the administrative director of the Mercaz HaRav yeshiva. After Rabbi Charlap died in 1952, he became Rosh Yeshiva until his own death. After the Six-Day War in 1967, he induced the Israeli government to approve the building of settlements in the West Bank and Gaza, and sent his students to that mission. He tried to strengthen the Chief Rabbinate, which he saw as the precursor of the future Sanhedrin.
He passed away in Jerusalem on Purim of 1982, and was buried in the Mount of Olives Jewish Cemetery.
Zvi Yehuda Kook