Between 1912 and 1919, the recently married Blisses resided in Paris, where Robert Bliss worked in the US embassy. It was there and in London that they began to collect artworks and decorative objects in earnest. Their early collecting interests often favored unusual objects that were newly available at the avant garde art dealers. These included medieval, Islamic, and Pre-Columbian artworks, which would become the foundation of their Dumbarton Oaks Collection.
Credit: Exhibition overview from museum website