[4] After serving as assistant to Wall Street corporation lawyer Victor Morawetz in the 1890s and early 1900s, Rublee entered public life when he became political adviser to Governor Robert P. Bass to establish La Follette-inspired reforms in New Hampshire (1910–12).
Rublee served on the U.S. delegation to the London Naval Conference in 1930, where he worked to promote U.S. cooperation with the Versailles treaty security system, and he was involved in several Latin American diplomatic missions during the 1930s.
His public work climaxed in 1938 when Franklin Roosevelt requested Rublee become director of the London-based Intergovernmental Committee on Refugees Coming, which attempted to arrange for the resettlement of German and Austrian Jews prior to the outbreak of World War II.
He negotiated an agreement with German diplomat Helmuth Wohlthat in February 1939 that would have permitted the emigration of 150,000 Jews, but it was never implemented due to the outbreak of the war in September.
Rublee divided his time between residences in Washington, New York City, and Cornish, New Hampshire, where he had a house in the artist and intellectual community that grew up around sculptor Augustus Saint-Gaudens' workshop at the close of the 19th century.