Maricopa County, named after the Maricopa Tribe, was created from portions of Pima and Yavapai counties in 1871. It was the fifth county formed in Arizona, and eventually portions were used to create Gila and Pinal counties.

In the late 19th century, citizens living far south of Prescott, the territorial capital and site of the Territorial Legislature, petitioned for a more local seat of government. Residents of the Salt River Valley and the Gila River area wanted a new county in their respective locations. After weighing both proposals, the legislature agreed with the Salt River Valley group and created Maricopa County. In 1889, Phoenix became the final site of the territorial capital and retains its status as Arizona’s capital city.

More than half of the state’s population resides in Maricopa County, which includes the cities of Phoenix, Mesa, Glendale, Scottsdale, Tempe, Chandler, Peoria and the town of Gilbert. This metropolitan area is the state’s major center of political and economic activity. In addition to housing the state capital, the county is home to a growing high-tech industry; manufacturing and agricultural industries; 15 institutions of higher learning, including Arizona State University and the Thunderbird Garvin School of International Management; various cultural attractions; major league professional basketball (Phoenix Suns and Phoenix Mercury), football (Arizona Cardinals), hockey (Phoenix Coyotes) and baseball’s 2001 World Champion Arizona Diamondbacks; and Phoenix Sky Harbor International Airport, fifth busiest in the world with over 1,300 daily flights.

Today Maricopa County measures 9,222 square miles, 98 square miles of which is water. Twenty-nine percent of this area is owned individually or by corporation, and 28 percent is owned by the U.S. Bureau of Land Management. The U.S. Forest Service and the State of Arizona each control 11 percent of the county; an additional 16 percent is owned by other public entities. Almost 5 percent is Indian reservation land.