Judah Leon Magnes (born July 5, 1877, San Francisco—died Oct. 27, 1948, New York City) was arabbi, religious leader, prime founder and first president of theHebrew University of Jerusalem, and aZionist who came to favour a binational Arab–Jewish state.

A graduate of theUniversity of Cincinnati (A.B., 1898), Magnes attendedHebrew Union College and was ordained as a rabbi in 1900. He then travelled toGermany for further studies. After receiving a Ph.D. from theUniversity of Heidelberg in 1902, Magnes returned to theUnited States and in 1904 became rabbi of a Reform synagogue, Temple Israel of Brooklyn. From 1905 to 1908 he was secretary of the Federation of American Zionists. In 1906 he assumed the pulpit of the Reform temple Emanu-El inNew York City. His many speaking engagements on behalf ofZionism, as well as hiseloquent sermons, made him a revered figure among American Jews. He foundedQehilla (Community) to unite thedisparate elements ofNew York Jewry; its Bureau of Jewish Education (1910–41) had a profound effect for decades. A growing dissatisfaction with Reform Jewry’s latitudinarian observance of ritual and custom caused Magnes to resign from Emanu-El in 1910 and accept the pulpit of Temple B’nai Jeshurun, an Orthodox congregation.

DuringWorld War I Magnes was a pacifist and, in addition, drifted away from Zionism, whose leaders supported the Allied war effort. He joined theJoint Distribution Committee, which, unlike the Zionists, emphasized relief to Jews in Palestine rather than political activism there.

At the war’s end he went to Palestine and subsequently joined one of the many committees founded by the Zionist movement to establish the Hebrew University of Jerusalem. Magnes soon became the guiding spirit of this effort. He raised funds,devised the university’s academic program, and, when the institution was completed at Mt. Scopus in 1925, became chancellor. In 1935 he became the first president of the university, a post he retained until his death, which occurred while on a visit to New York.

Magnes also foundedIḥud (Unity), an association dedicated to the advancement of Arab–Jewish reconciliation, and advocated an Arab–Jewish state that would be part of an Arab Federation. He worked in Iḥud with the renowned religious philosopherMartin Buber.