1. Cinco de Mayo: May 5 is known as Cinco de Mayo, a celebration of Mexican heritage and pride. It commemorates the Mexican army's victory over the French at the Battle of Puebla in 1862. This celebration is especially significant in Arizona, with its close proximity to the Mexican border and large Hispanic population.

2. Arizona Statehood: Arizona became a state on February 14, 1912, but on May 5, 1915, Governor George W.P. Hunt signed the Arizona State Flag Bill, officially adopting the state flag. The flag features a copper-colored star, representing Arizona's copper industry, on a blue field with gold and red rays symbolizing the sunshine and Arizona's beautiful sunsets.

3. Tragic Fire: On May 5, 1917, one of the deadliest fires in Arizona's history occurred in the town of Jerome. A fire broke out at the Connor Hotel, and due to strong winds, the fire quickly spread to surrounding buildings. The fire destroyed most of the town, leaving only a few homes and businesses standing.

4. Union Strike: In 1919, on May 5, 15,000 miners went on strike in Bisbee, Arizona, to protest low wages, long hours, and unsafe working conditions. Sheriff Harry Wheeler, along with a group of vigilantes, rounded up 1,200 miners and deported them to New Mexico, in what became known as the Bisbee Deportation.

5. First Women Jury: On May 5, 1934, Arizona made history by becoming the first state to allow women to serve on juries. Arizona Governor Benjamin Moeur signed the legislation into law, paving the way for women's civil rights in the United States.