Julian William Mack (July 19, 1866 – September 5, 1943) was a United States federal judge and social reformer.
Early life and education
Born in San Francisco, California, to William J. Mack and Rebecca M. (Tandler) Mack, he was raised in Cincinnati, Ohio, attending the public schools there from 1873 to 1884. He received a LL.B. from Harvard Law School in 1887, and was awarded a Parker Fellowship by Harvard University, attending the Universities of Berlin and Leipzig from 1887 to 1890. He married Jessie Fox on March 9, 1896. They had one daughter.
Mack was admitted to the Illinois bar in 1890 and was in private practice in Chicago from 1890 to 1895. In 1895, he secured an appointment as a professor of law at Northwestern University. He transferred to the University of Chicago in 1902 and there remained until his retirement in 1940. During his time in Chicago Mack became a member of the city's leading Jewish Reform congregation, Chicago Sinai congregation. Encouraged by its rabbi, Emil G. Hirsch, Mack became the leading manager of the United Hebrew Charities of Chicago during the 1890s.
Mack was very active in civil service in Chicago. He served as civil service commissioner in 1903; circuit court judge for Cook County, 1903-11. He founded Chicago's first juvenile court in 1904, which was located across the street from Jane Addams's Hull House, and was the judge for the court until 1907. Mack served as a judge of the Cook County Circuit Court from 1904 to 1905 and the First Illinois District Appeals Court from 1905 to 1911.
Federal judicial service
On December 12, 1910, Mack was nominated by President William Howard Taft to a joint appointment to the United States Court of Appeals for the Seventh Circuit and the United States Commerce Court, both new seats having been created by 36 Stat. 539. Mack was confirmed by the United States Senate on January 31, 1911, and received his commission the same day. The Commerce Court was abolished on December 13, 1913, but Mack continued his Court of Appeals service on the Seventh Circuit. On July 1, 1929, he was reassigned as an additional judge to the United States Court of Appeals for the Sixth Circuit and the United States Court of Appeals for the Second Circuit. On July 1, 1930, he was reassigned to serve solely on the Sixth Circuit. Mack assumed senior status on September 6, 1940, serving in that capacity until his death.
Other civic activities
During World War I, he served on the Commission of Labor of the Council of National Defense, the National War Labor Board, and the War Department's Board of Inquiry on Conscientious Objectors. He also organized Jewish war relief.
Julian Mack was one of the founders of the American Jewish Committee in 1906. His Jewish charitable work included serving as president of the Palestine Endowment Funds, honorary president of the World Jewish Congress, president of the American Jewish Congress, Zionist Organization of America, and various other organizations. He attended the Versailles Conference as an advocate for a Zionist state in Palestine. Kibbutz Ramat ha-Shofet, founded in Israel in 1941, was named in his honour. 
His social work included heading the National Conference of Social Work, the Immigrants Protective League (organized by Grace Abbott), the Infants' Welfare Society, Children's Hospital Society, and other organizations. He was a member of many clubs, a lifelong Democrat, and lived in New York City.
He died on September 4, 1943, in New York, New York.
- Julian Mack at the Biographical Directory of Federal Judges, a public domain publication of the Federal Judicial Center.
- Who's Who on the Web, s.v. "Julian William Mack" (n.p.: Marquis Who's Who, 2005)
- 6th Circuit biography of Julian Mack
- Barnard, Harry (1974). The Forging of an American Jew: The Life and Times of Judge Julian W. Mack. New York: Herzl Press.
- Brinkmann, Tobias (2012). Sundays at Sinai: A Jewish Congregation in Chicago. Chicago: University of Chicago Press. ISBN 9780226074542.