1. Montana became a state: On May 9, 1889, Montana officially became a state, making it the 41st state in the United States. The state's admission into the Union was a result of the Homesteading Act, which encouraged settlers to move west and establish homes on federal land.

2. Montana held its first election: On May 9, 1893, Montana held its first statewide election. Women were granted the right to vote in Montana a year earlier, making it the first state to give women the right to vote in state elections.

3. Fort Peck Dam construction began: On May 9, 1933, construction began on the Fort Peck Dam, the largest hydraulically filled dam in the world at the time. Built by the Civilian Conservation Corps, the dam served as a major part of the New Deal program to spur job creation and economic recovery during the Great Depression.

4. Montana's deadliest earthquake: On May 9, 1958, Montana experienced its deadliest earthquake on record. Measuring 7.5 on the Richter scale, the earthquake struck southwestern Montana and caused widespread damage and loss of life.

5. Wildfires ravage Montana: On May 9, 2000, a series of wildfires started in Montana, fueled by drought conditions and high winds. Over the course of the summer, the fires destroyed thousands of acres of forest land and led to the evacuation of many towns and cities across the state.