The Blisses' social circle in Paris included Edith Wharton, Walter Gay, and Royall Tyler.

Robert Bliss was instrumental in arranging for a series of important diplomatic meetings to take place at Dumbarton Oaks (see below) in the late summer and early fall of 1944.

The delegates deliberated over proposals for the establishment of an organization to maintain peace and security in the world, and their outcome was the United Nations Charter that was adopted in San Francisco in 1945.

[3] Robert Bliss was particularly enamored of pre-Columbian art, stating that when Tyler introduced him to it in a Parisian shop in 1912, "the collector's microbe took root in ... very fertile soil."

They set about renovating and enlarging the house, adding to the grounds, and building a series of terraced gardens on the 54-acre estate.

[4] They also continued to build their art collection, and upon retiring in 1933 to Dumbarton Oaks they began to lay the groundwork for a museum and research institute.

In 1935, Robert Bliss traveled through the highlands and tropics of Mexico, Guatemala, and Honduras to see Maya ruins with Frederic C. Walcott (1869–1949), a trustee of the Carnegie Institution of Washington.

In 1940, the Blisses cofounded the Dumbarton Oaks Research Library and Collection, which they endowed and gave to Harvard University.