1. The Jamestown Tornado: On April 15, 1887, a devastating tornado ripped through Jamestown, North Dakota, killing 14 people and injuring over 60. The tornado destroyed much of the town, causing over $250,000 in damage (equivalent to over $6 million today).

2. North Dakota becomes a state: On April 15, 1889, President Benjamin Harrison signed the bill that made North Dakota (along with South Dakota) the 39th state in the Union. A parade was held in Fargo to celebrate the historic occasion.

3. The sinking of the Titanic: Although not directly related to North Dakota, April 15 is also the day that the Titanic hit an iceberg and sank in the Atlantic Ocean in 1912. The tragedy had a profound impact on the world, including North Dakota.

4. The start of the Dust Bowl: On April 15, 1935, one of the worst dust storms in history struck the Midwest, marking the beginning of the Dust Bowl. North Dakota was one of the states hit hardest by the drought and dust storms that followed.

5. Oil discovered in North Dakota: On April 15, 1951, an oil well was drilled near Tioga, North Dakota, marking the beginning of the state's oil boom. The discovery led to increased exploration and drilling throughout the state, making North Dakota a major player in the energy industry.