The law regulating the printing of brand books was passed by the first session of the territorial legislature in 1851. Auxiliary recorders used them to help prevent duplication of brands assigned to individual livestock owners, and as a means of identifying and controlling animals that had been put into estray pounds or that were being sold in each county. Later, as regulations expanded state control over inspection for disease, transportation, and slaughter of livestock, maintenance of a central brand registry became even more important in the regulatory process. Subsequent revisions of the 1851 law expanded the list of officials who were to automatically receive the brand books, provided for public distribution, and changed the frequency of its publication.
Livestock is assumed to include all types of animals raised for pleasure or for profit.
Subsequent revisions of the brand law expanded the definition of livestock to include several other animals. The first surviving book in the series is an 1874 cumulation that records all brands that had been issued in the territory since 1851. A second cumulative brand book was published in 1884 covering the previous ten years, followed by several supplements. The practice of regularly rerecording brands every ten years started in 1901. The pattern was to publish a cumulative issue with supplementary books published more frequently that would include all new brands registered since publication of the chem.