In 1921, the yeshiva moved back to its original facilities in Mir, where it remained until Nazi Germany invaded Poland in 1939 marking the beginning of the Holocaust.

Several smaller yeshivos managed to escape alongside the Mir, and, despite the difficulties involved, the overseers of the Mirrer yeshiva undertook full responsibility for their support, distributing funds and securing quarters and food for all the students.

A short time later, the yeshiva relocated again, to (Japanese-controlled) Shanghai, China, where they remained until the end of World War II.

The heroism of the Japanese consul-general in Lithuania, Chiune Sugihara,[1] who issued several thousand transit visas to Jews, permitting them to travel in order to flee to Japan, has been the subject of several books.

The yeshiva settled in New Lots section of East New York before moving to their current location on Ocean Parkway in Flatbush.

Mayor Michael Bloomberg issued a statement praising Berenbaum, noting that he built the Jewish academy "into one of the largest centers for Torah study in the world."