Rosika Schwimmer (1877-1948) was born in Budapest, Hungary, the oldest child of Max B. Schwimmer, a grocer and horse dealer, and Bertha Katscher Schwimmer, member of a distinguished Jewish literary family. She married in 1911 but divorced two years later. An accomplished linguist, fluent in more than half a dozen languages, Schwimmer initially devoted herself to the cause of woman suffrage. She attended the 1904 Berlin meeting of the International Council of Women at which the International Women's Suffrage Alliance was founded. She settled in London in 1911 as press secretary of the Alliance. With the outbreak of World War I, Schwimmer focused her efforts on peace. In 1914 she traveled to the U.S. to speak with President Wilson and Secretary of State William Jennings Bryan on behalf of the Alliance's endorsement of neutral mediation of the war. Her flamboyant personality and ardent peace advocacy provided the spark that kindled sentiment for the Woman's Peace Party. She was also influential in organizing the 1915 Congress of Women at The Hague and establishing the International Committee of Women for Permanent Peace (later Women's International League for Peace and Freedom (WILPF)). The Ford Peace Ship, the ocean liner sponsored by Henry Ford that sailed to Europe in 1915-16 carrying an unofficial mediation commission, brought its passengers, including Schwimmer, a notoriety that led to her resignation from WILPF in 1918. Upon her return to Hungary, Schwimmer was appointed ambassador to Switzerland. In 1921 she returned to the U.S. where her attempts to resume her career and gain citizenship were thwarted by accusations that she was a spy. Her final citizenship application was denied in 1924 when she refused to affirm her willingness to bear arms in defense of the United States. She remained in the U.S. as an alien for the rest of her life, supported by her old friend and co-worker for peace, Lola Maverick Lloyd.

Lola Maverick Lloyd (1875-1944) graduated from Smith College in 1897. A pioneer suffragist and pacifist, in 1915 she co-founded with Jane Addams the Women's Peace Party, and later the Women's International League for Peace and Freedom. She was also a delegate to the Congress of Women at the Hague in 1915 and sailed on Henry Ford's Peace Ship. Lloyd and Schwimmer co-chaired the Campaign for World Government.