Eliza Bowditch van Loon was a member of the Bowditch family of Boston. Her father was Henry Pickering Bowditch (1840-1911), a renowned medical professor and researcher at the Harvard Medical School. She married Hendrik Willem van Loon, a Dutch citizen who had studied at Cornell University, and who became an AP correspondent in Moscow in 1906. After living in Moscow for several months, the van Loons moved to Warsaw in September of 1906 when Hendrik was re-assigned.
From the guide to the Papers, 1906-1907, (Schlesinger Library, Radcliffe Institute)