Although little known today, the name of William Alexander Leidesdorff is enshrined on streets in San Francisco and a town along the American River. He was also one of California’s pioneers of African descent and instrumental in bringing about the American annexation of California.

Early Life and Ancestry

Much of the information that we have about William Leidesdorff’s biography comes from the historian Hubert Howe Bancroft. In his History of California, Bancroft mentions Leidesdorff several times as a key contributor to the state’s early history.

Leidesdorff was born in 1810 in San Croix in the Virgin Islands, which were at the time known as the Danish West Indies. His father was a Danish sugar planter, William Leidesdorff, Senior. His mother, Anna Marie Sparks, a was a native woman of African descent.

Arrival in California and Business Ventures

We know little about his early life. According to Bancroft, at the age of 30 or 31, young William made his way to Alta California. He was a very astute businessman, and thanks to his facility with multiple languages, was liked and respected by Mexicans and Anglo-Americans alike.

In 1844, he became a Mexican citizen and obtained a grant of land, which he named Rancho Rio de los Americanos. The grant was for approximately 35,000 acres, on what is today the American River near Sacramento. His rancho was adjacent to the one owned by John Augustus Sutter.

Leidesdorff engaged in multiple business activities, including the hide and tallow trade, the basis of the rancho economy in Alta California.

Leidesdorff and the Annexation of California

Starting in 1845, he was asked to serve as the US Vice Consul to Mexico. The consul was a man named Thomas Oliver Larkin, who had a great interest in bringing California into the United States and who saw Leidesdorff as an excellent ally in his efforts.

Thanks to his business success, Leidesdorff became one of the main financiers of Captain John Fremont and his men who helped support the U.S. annexation of California.

After the war, Leidesdorff wrote to the US government asking for reimbursement for the money that he put out to help support Fremont and his volunteers who came down into Alta California. It is fascinating to read his correspondence with the US government after the war. In it Leidesdorff gives an eloquent accounting of the money he spent aiding Fremont, for which he expected to be reimbursed. Leidesdorff was unsuccessful and the U.S. government never repaid him. Nevertheless, the letters reveal a gread deal of facility and persuasiveness in English, which was not his native tongue.

Other Accomplishments

Leidesdorff was a visionary in transportation, who launched the first steamboat to operate on both the San Francisco Bay and the Sacramento River. He purchased the 37 foot long steamboat in Alaska and brought it down to California, demonstrating his resourcefulness and entrepreneurial spirit.

As an entrepreneur, Leidesdorff was one of the men who built San Francisco. He was not only one of the town’s most prominent businessmen, but he was a member of the city council, its treasurer, and a member of the school committee, taking an active part in local politics during his short life.

In addition to his civic involvements, Leidesdorff was instrumental in bringing entertainment to the newly formed state of California. He staged the state’s first horse race near Mission Dolores in 1847, showcasing his dedication to providing cultural experiences for the people of San Francisco.

Death

In 1848, William Leidesdorff contracted a deadly illness. Doctors described it as “brain fever,” which may have been meningitis, scarlet fever, typhoid, fever, or encephalitis. On May 18th of that year, he died. He was only 38 years old. His body was buried at Mission San Francisco de Asís (Mission Dolores) in San Francisco. Today both the city of San Francisco and the town of Folsom (where his land grant was located) have streets dedicated to him.

Had he lived longer, who knows what else William Alexander Leidesdorff might have accomplished?

Further Reading

William Alexander Leidesdorff – First Black Millionaire, American Consul and California Pioneer by Gary Palgon.