A leading Canadian volunteer community worker, Saidye Bronfman was born in Plum Coulee, Manitoba on December 20th, 1896. She grew up there and in Winnipeg. Her father, Samuel Rosner (1871–1952), a prosperous businessman born in Bessarabia, who came to Canada by way of England in his late teens, served as mayor of Plum Coulee for two years. Her mother, Priscilla Berger Rosner (1876–1951), an immigrant to Canada from Odessa, was a homemaker. Two years after Saidye’s marriage in 1922 to Samuel Bronfman (1891–1971), the driving force behind the Joseph E. Seagram liquor distillers and distributors and on his way to becoming one of the wealthiest Canadians of his day, the couple moved to Montreal.

Born into privilege and married into great wealth, Bronfman lived by the principle of noblesse oblige. It was also the case that a demonstrable community conscience gave a boost to those eager to climb the social ladder, especially Jews who lacked a pedigree and found acceptance in Canada’s prejudiced society hard to attain. Even before her marriage, Bronfman had served as president of the Girls’ Auxiliary of the Winnipeg Jewish Orphanage Society. Later she headed the Orphans’ Home. In Montreal, she began her community work in 1929 with the Young Women’s Hebrew Association (YWHA), which she served as president for six years. She was the founder and president of the Women’s Division of the Combined Jewish Appeal (1931–1933) and in 1934 one of the founders of Canadian Youth Lit. "ascent." A "calling up" to the Torah during its reading in the synagogue.Aliyah, the Hadassah organization’s program to resettle German-Jewish youngsters in Palestine.

During World War II Bronfman’s good works complemented those of her husband. Among other things, Sam, together with another donor, gave a submarine chaser, the HMCS Montreal II, to the Royal Canadian NavyAlready at the beginning of the war, Saidye Bronfman had organized the Jewish Branch of the Quebec Provincial Division of the Canadian Red Cross Society. That Jewish women should work for the Allied cause apart from gentiles was suggested by Margaret Shaughnessy, a prominent Montreal Red Cross leader. Whatever the latter’s motives, the Jewish women worked effectively under Bronfman’s leadership. In 1943, her contributions to the war effort and those of her husband were recognized by King George VI with the award to her of the Order of the British Empire (OBE). While the honor was undoubtedly deserved, it was probably given to her and not to her husband because of the odor of rum running and other improprieties that had attached to him in his early years in the liquor business.

In the postwar period, both Jewish and general institutions in Canada and the United States benefited from Saidye Bronfman’s experience, financial support, and name. Among the Jewish groups with which she was associated were the Allied Jewish Community Services of Montreal (honorary president), the National Council of Jewish Women (vice-president), the Women’s Auxiliary of the Montreal Jewish General Hospital (vice-president and life member), the Priscilla Rosner Chapter of Hadassah-wizo (honorary patron), the Canada-Israel Cultural Foundation (honorary patron), the Jewish Community Foundation of Greater Montreal (member of the advisory council), the Jewish Federation of New York (committee member), and the Samuel and Saidye Bronfman Family Foundation (president). Organizations she actively supported in the wider community included the Save the Children Fund (member of the Founders Committee and honorary vice-president), l’Hopital Sainte-Juste and the Fondation Justine-Lacoste-Beaubien (life governor), the Montreal Symphony Orchestra (president, Ladies Committee), the Museum of Modern Art in New York (member, International Council), and the New York Philharmonic Society (Women’s Committee executive committee).

From 1924, the Bronfmans lived primarily in Montreal, although they maintained a large estate in Tarrytown, New York in the 1950s and early 1960s. They were the parents of four children: Aileen Mindel (Minda de Gunzburg, 1925–1985); Phyllis Lambert (b. 1927), the founding director of the Canadian Centre for Architecture in Montreal; Edgar Miles (b.1929), for many years head of Seagram’s American operations and president of the World Jewish Congress; and Charles Rosner (b.1931), the long-time head of Seagram’s Canadian operations, the founder of the CRB Charitable Foundation, and one of the initiators of the Birthright program for young Jewish adults. Saidye Bronfman died in Montreal on July 6th, 1995. In 2004, only her daughter Phyllis remained in Canada.