The town of Newhall is named after Henry Mayo Newhall, a businessman who became rich during the California Gold Rush. At first, he founded H.M. Newhall & Company, an auction house in San Francisco. Then, he got into the railroad business. He put money into companies that would join San Francisco to other cities and was in charge of the San Francisco and San Jose Railroad. He sold the business to the Southern Pacific Railroad in 1870, and was one of the people in charge of it.