Aaron M. Wright, Ph.D.
As the country celebrates its 250th anniversary, it helps to put Arizona’s history in context. Arizona wasn’t part of the United States until acquired from Mexico in the mid-1800s. In 1776, as eastern colonies were signing the Declaration of Independence, the Tucson’s Spanish presidio was less than a year old, and Yavapai County remained uncharted territory.

But Arizona has a 250th anniversary to commemorate. The National Park Service calls it Anza250—marking a colonizing expedition from the Province of Sonora to the San Francisco Bay region, the northern reach of New Spain. Led by Spanish Captain Juan Bautista de Anza, the 1,800-mile journey from late 1775 to mid-1776 included about 250 people—mostly soldiers and their families—and roughly a thousand head of cattle. Remarkably, only one person died, while three were born, meaning the party grew during what must have been a grueling trek.