1. In 1883, the Northern Pacific Railroad reached Bismarck, making it the first transcontinental railroad to reach the city.

2. On May 21, 1910, Theodore Roosevelt delivered a speech in Aberdeen, North Dakota, advocating for the conservation of natural resources and the establishment of national parks.

3. In the early morning hours of May 21, 1951, the town of Fargo experienced a devastating tornado that killed 12 people and injured over 100 others.

4. On May 21, 1980, a major oil spill occurred on the Yellowstone River in Montana, devastating wildlife and ecosystems along the river, including parts of North Dakota.

5. In 2011, North Dakota Governor Jack Dalrymple signed into law several bills aimed at boosting the state's economy, including a bill that phased out the state's corporate income tax over the course of several years.