[1][2] As soon as word of the mid-century gold finds in California reached New York, Phelps took a boat to the west coast.

[1] Failing to find a fortune in gold, he moved to San Francisco to resume a career in the mercantile,[1] starting a merchant house in August 1850.

[citation needed] He used the land for farming and soon decided to make the area, now the city of San Carlos, his home.

[3] Living in San Carlos, in 1851 Phelps became involved in the local vigilance committee in an effort to uphold the law.

[2] During the 1859 Republican California state convention, his name was advanced as a potential nominee for governor, but he withdrew in favor of Leland Stanford.