Darius Ogden Mills (September 25, 1825 – January 3, 1910) was a prominent American banker and philanthropist.

[2] Shortly after his father's death in 1841,[5] he began working as a clerk in a small general store in New York City at the age of 15.

[2] In August 1884, Mills, Alvinza Hayward, a San Francisco mining tycoon, and several other investors purchased 720 acres encompassing a mineral spring in Saratoga, California the chemical content of which was almost identical to Saratoga Springs, New York for a reported $2,000.

In 1866, they opened the 14-room Congress Hall to great local acclaim, and in 1872 sold the property to Lewis P Sage and son for approximately $25,000.

[9] Also in 1864, with other investors, he founded the Bank of California, which grew large in the 1860s and 1870s, but collapsed due to financial irregularities involving its chief cashier, William Chapman Ralston.

[3] Together, they had a son and a daughter:[15] He died of a heart attack in 1910 at his Millbrae home, leaving an estate worth $36,227,391 (~$857 million in 2023).

The California State Capitol rotunda houses a statue donated by Mills that depicts Queen Isabella financing Christopher Columbus's initial voyage.