Born on February 27, 1865, in Nashville, Tennessee, Mary Isom grew up and attended public schools in Cleveland. She attended Wellesley College for a year, 1883╨1884, but ill health prevented her completing her education. In 1899, following the death of her widower father, she entered the Pratt Institute Library School in Brooklyn, New York, from which she graduated in 1900. The next year she took the job of cataloger of the newly acquired John Wilson Collection at the Library Association, a private subscription library in Portland, Oregon. In January 1902 she was appointed librarian of the institution, which at that time was converted to a free public library. To the burden of organizing a greatly expanded library to serve a similarly multiplied community of users was added a year later the responsibility, mandated by state law, of making the library available to all the rural communities of Multnomah County. Within five years she had established a network of three branch libraries and eleven reading rooms around the county along with an efficient book circulation system.
In 1904 Isom organized the Oregon Library Association, and in 1905 she was principally responsible for the passage of legislation creating the Oregon State Library Commission, of which she was a member until her death. She helped found the Pacific Northwest Library Association in 1909 and served as its president in 1910╨1911. In 1912╨1913 she was second vice-president of the American Library Association. The rapidly growing demands on the Portland library made necessary the establishment of seven large permanent branches in 1911╨1913, and in the latter year, crowning a long period of deep involvement in every phase of the project, she saw opened the new Multnomah County Public Library. During World War I she was active in organizing libraries for hospitals and army and lumber camps in Oregon and Washington. For six arduous months she organized hospital libraries in France. In declining health in her last years, she continued her work until her death in Portland, Oregon, on April 15, 1920.
