Blackhawk, California
census-designated place in Contra Costa County, California, United States
Blackhawk is an unincorporated planned community and census-designated place located in Contra Costa County, California, United States, east of Danville and Oakland. As of the 2020 census it had a population of 9,637. Governed by county rules/regulations and a homeowner association (HOA), Blackhawk has a country club, two golf courses, sports complex, restaurants, and abuts the Blackhawk Plaza mall. HOA dues provide 24-hour security plus additional law enforcement contracted through the Contra Costa County Sheriff's Office. The area is covered by the San Ramon Valley Fire Protection District. The ZIP code is 94506. The community is inside area code 925.
Blackhawk Ranch
Blackhawk Ranch was established in 1917 by Ansel Mills Easton and his son-in-law William Q. Ward, in an area east of the San Ramon and Sycamore Valleys. The name came from an Irish racehorse named Blackhawk that Easton's family had once owned (who in turn was named for the Sauk chieftain Black Hawk). The land passed through the hands of several owners, including Raymond Force (the owner of the Caterpillar Tractor Company), the Hawaii-based sugar and pineapple company Castle & Cooke, and Howard Peterson (owner of Peterson Tractor).
“Blackhawk, California” enters the record as census-designated place in Contra Costa County, California, United States. Crown Archives preserves that source wording while asking what Blackhawk, California and census-designated can confirm, complicate or overturn.
Why this record matters
“Blackhawk, California” is worth following because a concise public description often conceals a longer documentary argument. Here, Blackhawk, California and census-designated provides the most credible route into that argument.
Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Sep 7, 2026. The linked authority identifier is Q3470840. VIAF identifies the subject as 139751240. The Library of Congress control number is n2002125645. Authority coordinates are 37.821, -121.908. 1 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2020 and 1917.
Modern boundaries and familiar names can conceal earlier jurisdictions or structures that do not align with the present site. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Blackhawk, California”, its source revision and the description used here.
- Expand the search: follow Blackhawk, California primary sources, Blackhawk, California archive and Blackhawk research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Blackhawk, California”?
- Which authority defined the place, boundary or structure at the relevant date?
- Which earlier names or jurisdictions may reveal additional records?
Search terms from this dossier
This entry incorporates text from “Blackhawk, California” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.