Eliezer Yehuda Finkel, also known as Reb Leizer Yudel Finkel, (1879–1965) was the Rosh Yeshiva (dean) of the Mir Yeshiva in both its Polish and Jerusalemic incarnations.
In 1903 Finkel married Malka, the daughter of Rabbi Eliyahu Boruch Kamai who was the Rosh Yeshiva of the yeshiva in Mir, Belarus. Three years later he joined the staff of the Mir Yeshiva, and in 1917 became its Rosh Yeshiva upon the death of his father-in-law.
During the interwar period, the Mir Yeshiva's enrollment grew close to 500 students from all over the world. During this time Finkel chose one of his students, Rabbi Chaim Leib Shmuelevitz as a son-in-law and eventually successor.
World War II and after
With the outbreak of World War II, the yeshiva was forced into exile and eventually it found refuge in Kobe, Japan and Shanghai, China. While the student body, led by Rabbi Chaim Shmuelevitz eventually relocated to the United States (see Mir Yeshiva (Brooklyn)), Finkel established a new branch of the Mir Yeshiva in Jerusalem with a handful of advanced Talmudic students from Etz Chaim Yeshiva.
Later Shmuelevitz came to Jerusalem to be Rosh Yeshiva under his father-in-law. One of Finkel's sons, Rabbi Beinish Finkel succeeded his brother-in-law Shmuelevitz as Rosh Yeshiva upon the latter's death in the 1979.
He founded other yeshivas, including the original yeshiva of Yitzchok Zev Soloveitchik, to whom he sent some of his top students.