1. In 1851, the first recorded steamboat journey on the Willamette River took place. The boat, called the Lot Whitcomb, traveled from Oregon City to Portland and marked a significant development in the transportation industry of the state.

2. On May 21, 1880, the Oregon State Penitentiary officially opened. It was the second prison established in the state and housed inmates until it was closed in 2011.

3. The Oregon State Capitol building was dedicated on May 21, 1938. The 121-foot-tall building is located in Salem and serves as the workplace for the governor, secretary of state, and treasurer, among others.

4. In 1980, the eruption of Mount St. Helens occurred in nearby Washington state, resulting in widespread ashfall across much of Oregon. The ashfall caused significant damage to crops and livestock in the agricultural industry.

5. May 21, 1998, marked the start of the 24-day standoff between law enforcement and members of the Montana Freemen militia in Jordan, Montana. The event drew national attention and ultimately resulted in the arrest and prosecution of more than a dozen militia members.