William Brainard Post was born in Connecticut in 1830, and arrived in Monterey in 1848 at the age of 18. He worked at the whaling station at Point Lobos for two years then became a foreman on the Soberanes ranch, Rancho San José y Sur Chiquito, where he met a Mission Indian girl named Anselma Onesimo (the sister of Loreta Meadows, who married James Meadows). They were married in 1850.
Post established a grain warehouse at Moss Landing, served as a steamship agent, operated a butcher shop in Castroville, and in the 1860s homesteaded in the Big Sur area later to become known simply as "Posts."
Descendants of the family still live there.
- Clark, Donald T., Monterey County Place Names (Kestrel Press, Carmel Valley, 1991).