1. Montana became a state on March 4, 1889, joining the Union as the 41st state. The state's admission was the result of the Montana Enabling Act, which was signed into law by President Benjamin Harrison on February 22, 1889.

2. On March 4, 1908, the first airplane flight in Montana history took place in Helena. The flight, which was piloted by French aviator Louis Paulhan, drew a crowd of 20,000 spectators and marked a major milestone in the history of aviation in Montana.

3. March 4, 1942, was a significant day for Montana's Japanese-American population. On that day, President Franklin D. Roosevelt signed Executive Order 9066, which authorized the internment of Japanese-Americans living on the West Coast. Many of these individuals were sent to internment camps in Montana, including the Fort Missoula Internment Camp.

4. In 1978, Montana Governor Thomas L. Judge declared a state of emergency on March 4 due to a severe winter storm that had caused widespread damage across the state. The storm, which lasted from March 1-6, dumped over 30 inches of snow in some areas and led to numerous road closures and power outages.

5. March 4, 1986, marked the beginning of a major environmental disaster in Montana's Clark Fork River. On that day, a tailings dam at the site of the Anaconda Copper Mine near Butte ruptured, releasing millions of gallons of toxic waste into the river. The disaster has had long-lasting impacts on the river's ecosystem and serves as a reminder of the need for responsible environmental practices.