1. Lewis and Clark Expedition: On May 29, 1805, explorers Meriwether Lewis and William Clark set out from Camp Dubois in present-day Illinois to begin their journey westward to the Pacific coast. Along the way, they would encounter and document many fascinating aspects of Montana's natural history and Native American cultures.

2. Montana Statehood: On May 29, 1889, President Benjamin Harrison signed the act that officially admitted Montana as the 41st state of the United States. In the decades that followed, Montana would play a pivotal role in the nation's economic, political, and environmental affairs.

3. Butte Mining Disaster: On May 29, 1917, an explosion at the Granite Mountain and Speculator mines in Butte killed 168 miners, making it one of the worst mining disasters in American history. The tragedy sparked national outrage and led to major reforms in mine safety regulations.

4. The Anaconda Road Massacre: On May 29, 1920, members of the Industrial Workers of the World (IWW), a radical labor union, clashed with law enforcement officials on the Anaconda Road near Butte. The ensuing violence left one IWW member dead and several others wounded, and marked a turning point in the struggle for workers' rights in Montana and beyond.

5. Ryan Dam Construction: On May 29, 1985, construction officially began on the Ryan Dam hydroelectric project on the Missouri River near Great Falls. The project, which was completed in 1989, provided a significant source of renewable energy for the surrounding area and helped to spur economic development in the region.