In 1851 the U.S. Congress passed "An Act to Ascertain and Settle Private Land Claims in the State of California" which required all holders of Spanish and Mexican land grants to present their title for confirmation before the Board of California Land Commissioners. Land from titles not confirmed became part of the public domain. This Act placed the burden of proof of title on landholders and initiated a lengthy process of litigation that resulted in most Mexican Californians, or Californios, losing their titles. While 604 of the 813 claims brought before the Board were confirmed, most decisions were appealed to U.S. District Court and some on to U.S. Circuit Court and the Supreme Court. The confirmation process required lawyers, translators, and surveyors, and took an average of 17 years to resolve. The records of the District Court cases, the Land Case Files, were deposited on permanent loan in The Bancroft Library by the U.S. District Court in 1961. There are 857 total cases: Northern District Cases 1-458 and Southern District Cases 1-399 (see "Additional Notes on the Collection" for a note on case number discrepancies). Materials include transcripts, witness depositions, materials presented as evidence, and other legal documents. Most maps were transferred to the Map Collection of The Bancroft Library for separate cataloging (see: Maps of private land grant cases of California).

In 1851, after the Mexican American War, the United States Congress created the Board of Commissioners to Ascertain and Settle the Private Land Claims in the State of California (commonly known as the Board of California Land Commissioners). The Board heard 813 cases between 1851 and 1856, and in 604 of those cases the titles were confirmed. Appeals could be made to U.S. District Court in San Francisco, then on to U.S. Circuit Court and U.S. Supreme Court. Confirmed titles were appealed as a matter of procedure -- all but 3 of the 604 cases confirmed by the Board were appealed to U.S. District Court. Between 1852 and 1892, 857 cases were brought to U.S. District Court, 458 in the Northern District and 399 in the Southern District (see "Information for Researchers" for a note on case number discrepancies). While the majority (97%) of these cases were resolved by 1885, a few cases were litigated into the 1940s. 94 cases appeared before the U.S. Circuit Court, and 114 before the U.S. Supreme Court. Because materials from cases appealed to the Circuit Court and and Supreme Court are interfiled with the District Court Cases, there are documents in the Land Case Files dated later than 1892. The full date range, including interfiled materials from higher courts, is 1852-1942. Of the 604 titles confirmed by the Land Board, 582 received patents.

Number of containers: 857 Cases. 876 Portfolios. 6 volumes (linear feet: Approximately 75) Microfilm: 200 reels 10 digital objects (1494 images)

The Land Case Files were placed on permanent deposit in The Bancroft Library by the U.S. District Court in 1961. All requests for permission to publish or quote from manuscripts must be submitted in writing to the Head of Public Services. Permission for publication is given on behalf of The Bancroft Library as the custodian of the physical items.

Portions of the collection are available on microfilm (see Container List). Please use microfilm when possible: BANC MSS C-A 300 FILM. Index to microfilm in Microfilm Binder 42.