Mary Julia Ledlie was born on January 26, 1848 in Springfield, Illinois to Julia Wynn and Frank Ledlie. In 1865, the family traveled from Illinois to the Gulf of Mexico where they boarded a ship to California—a journey that required a tedious overland crossing of the Isthmus of Panama. Once on the West Coast, the Ledlies settled in Sacramento where Frank took a job on a riverboat run by Captain James Monroe McDonald, an early West Coast settler. Not long after their arrival in California, Frank Ledlie passed away. In order to support themselves, Mary and her mother opened a boarding house which catered to sailors. In 1886, twenty years after arriving in California, Mary and her mother moved to San Francisco where they lived briefly before purchasing ranch land in Elsinore. In 1905 Mary was wedded to James McDonald, the man who had employed her father four decades earlier. In 1906 Mary’s mother passed away, followed a year later by James McDonald. Upon James’ death, Mary took control of his estate which included a mining operation, timber land in California and Oregon, and royalties from several patents for glass insulators used on telephone and power lines. From her homes in San Francisco and Palo Alto, Mary oversaw aggressive growth of the McDonald estate through wheat farming in San Luis Obispo County, spruce logging in Oregon, and a quicksilver mine in New Almaden.
Mary McDonald took great personal interest in the arts and sciences and was an active participant in California’s intellectual community. In the early 1900s, she provided funds for five scholarships and several endowed chairs at the University of California and supplied Pomona College with valuable books for use by faculty and students. She also donated heavily to the city of San Francisco, supporting a city orphanage and contributing to the 1915 Panama Pacific Exposition.