1. On May 12, 1848, Wisconsin held its first constitutional convention in Madison. The convention drafted the state's first constitution, which was later ratified by the people and became Wisconsin's governing document.

2. The Great Wisconsin Cheese Festival kicks off every year on the second Friday of May, which can fall on May 12th. Started in 2003, this festival celebrates Wisconsin's dairy industry and features a parade, cheese curd eating contest, and live music.

3. On May 12, 1958, the USS Wisconsin, a battleship named after the state, was commissioned into service. The ship saw action in the Korean War and Operation Desert Storm before being decommissioned in 1991.

4. Wisconsin native Mark Ruffalo was born on May 12, 1967. Ruffalo is best known for his acting roles in films such as "The Avengers" and "Zodiac," as well as his political activism on issues such as climate change and social justice.

5. The Wisconsin State Capitol building, located in Madison, was dedicated on May 12, 1917. The Capitol features a picturesque dome that is the largest granite dome in the world, and it houses the offices of the governor, lieutenant governor, and both chambers of the state legislature.