William H. Spurgeon, a Kentuckian, was looking for a suitable place to start a town. On October 10, 1869, he was riding on horseback across the land that would become Santa Ana. The land was covered with yellow mustard plants so tall that Spurgeon climbed a sycamore tree to view the area. Impressed with what he saw, he bought 74.2 acres from Jacob Ross, Sr., for $595. George Wright of Los Angeles was hired to design and lay out the town, and the map was plotted on December 13, 1870. The land had originally been part of a larger grant called Santiago de Santa Ana, so Spurgeon named the town Santa Ana.

Spurgeon spent the rest of his life developing his city. His artesian well and small tower supplied water for the residents, and paid for a road through the mustard fields to open up travel to Anaheim. He ran a small general store, but also served as postmaster (keeping the mail in a wooden shoe box). He became the first mayor when Santa Ana was incorporated on June 1, 1886, and presided over the town when it became the county seat of Orange County in 1889.