1. On September 17, 1923, the Gila River Indian Reservation was officially established through an executive order of President Calvin Coolidge. The reservation spans over 372,000 acres in central Arizona and is home to the Akimel O'odham and the Pee Posh tribes.

2. In 1862, a group of Apaches raided the small town of Tubac in southern Arizona. The raid resulted in the death of 12 settlers and the capture of several others. This event marked one of the many conflicts between European settlers and Native American tribes in Arizona during the 19th century.

3. On September 17, 1962, Arizona State University (ASU) opened its newly constructed campus in Tempe, Arizona. The campus was initially home to only 784 students, but has since grown into one of the largest public universities in the country.

4. In 1983, the state of Arizona ratified the Martin Luther King Jr. Holiday Bill, officially recognizing the third Monday in January as Martin Luther King Jr. Day. This made Arizona the first state in the country to create a state holiday honoring the civil rights leader.

5. On September 17, 1882, the town of Bisbee was founded in southeastern Arizona. Bisbee became known for its rich copper deposits and quickly grew into one of the largest mining towns in the state. Today, the town is a popular tourist destination and is home to many art galleries, museums, and historic landmarks.