Dating early Arizona maps by counties involves identifying changes in territorial and county boundaries. These boundaries evolved significantly from Arizona’s creation as a U.S. territory in 1863 through its statehood in 1912. These boundary changes and the development of counties offer essential clues to the age of historical maps.
Steps to Date Early Arizona Maps by Counties
1. Understand Arizona’s Territorial History
- Arizona Territory Creation (1863): The Arizona Territory was separated from the western half of the New Mexico Territory.
- Initially, the territory was divided into just four counties:
- Mohave County: Northwestern Arizona.
- Yuma County: Southwestern Arizona.
- Pima County: Southern Arizona, encompassing Tucson.
- Yavapai County: Northern Arizona, including Prescott (the first territorial capital).
- Maps before 1863 typically include Arizona within the New Mexico Territory.
2. Recognize Key County Formation Dates
Early maps of Arizona often feature new counties as they were created:
- Apache County (1879): Split from Yavapai County.
- Cochise County (1881): Carved out of Pima County.
- Graham County (1881): Formed from parts of Pima and Apache Counties.
- Gila County (1881): Split from parts of Maricopa and Pinal Counties.
- Navajo County (1895): Created from Apache County.
- Santa Cruz County (1899): Split from Pima County.
- Greenlee County (1909): Arizona’s last county before statehood, created from Graham County.
3. Examine County Boundaries and Names
- Shifts in Boundaries: Early maps may not align perfectly with modern boundaries. Changes often indicate the map’s age.
- County Names: Some county names have remained stable since their creation, aiding in identification.
4. Check Capitals and Cities
The location of county seats or major cities can date maps:
- Prescott served as Arizona’s capital until 1867 when Tucson became the capital. In 1889, the capital moved to Phoenix.
- Maps reflecting changes in the location of the capital are useful for dating.
5. Map Features as Time Markers
- Railroads: Early maps before 1881 will lack railroads; after 1881, the Southern Pacific Railroad and other lines start appearing.
- Reservations: The establishment of Native American reservations, especially the Navajo, Hopi, and Apache reservations, provides further clues.
6. Analyze Map Design and Publication Details
- Typography and Style: Early maps often used ornate typography and hand-drawn designs.
- Cartographers and Publishers: Names like Rand McNally, George W. Cram, and U.S. Geological Survey are common in later maps. Identifying the publisher can give a date range.
Example Key Maps and Periods:
- 1864: A map with only Mohave, Yavapai, Pima, and Yuma Counties is one of the earliest Arizona maps.
- 1881-1890: Maps including Cochise, Graham, Gila, and Apache Counties show territorial expansion.
- 1909: Maps showing Greenlee County show the latest territorial maps before statehood.
Tools for Dating Maps
- Historical Atlases: Compare maps to atlases from known periods.
- Library of Congress Map Collection: Features digitized maps from various periods, including early Arizona maps.
- Arizona State Archives: Holds detailed county formation records and historical maps.
- Digital Platforms: Websites like David Rumsey Map Collection or Old Maps Online can offer comparable samples.
By carefully examining county boundaries, formation dates, and map details, you can make a precise estimation. This approach lets you figure out the production date of early Arizona maps. Let me know if you’d like help analyzing a specific map!