Bar-Ilan was born in Volozhin, Russia, the son of Rabbi Naphtali Zevi Judah Berlin, who was the head of the famous yeshivah there. Meir later Hebraized his name. As a young man he joined the Mizrachi movement, representing it at the Seventh Zionist Congress (1905) at which, unlike the majority of Mizrachi delegates, he voted against the Uganda Scheme.

In 1911 he was appointed secretary of the world Mizrachi movement, working in Berlin; it was he who coined the Mizrachi slogan "Erez Yisrael le-am Yisrael al pi Torat Yisrael " ("The land of Israel for the people of Israel according to the Torah of Israel"). He moved to the United States in 1915, served as president of the U.S. Mizrachi, and from 1925 was a member of the Board of Directors of the Jewish National Fund.

In 1926 Bar-Ilan settled in Jerusalem where he played a leading role in the life of the Jewish community. He was a leading opponent of the Palestine partition plan in 1937, and of the British White Paper of 1939, and advocated civil disobedience and complete noncooperation of the Jewish population with the British authorities. After the establishment of the State of Israel, he organized a committee of scholars to examine the legal problems of the new state in the light of Jewish law. He also founded an institute for the publication of a new complete edition of the Talmud. Bar-Ilan University near Tel Aviv, founded by the American Mizrachi movement, is named in his honor, as is the Meir Forest in the Hebron hills, and the moshav Bet Meir near Jerusalem.

His older brother, Hayyim Berlin (1832--1912) was also a famous rabbi. He served in several Russian towns and in 1906 settled in Jerusalem where he was appointed Chief Rabbi in 1909. A yeshivah in New York is named after him.

Entry taken from "Junior Judaica, Encyclopedia Judaica for Youth" CD-ROM

by C.D.I. Systems 1992 (LTD) and Keter.