1. Statehood Day: April 15, 1867 marks the day that Nebraska became the 37th state in the United States. It is celebrated as Statehood Day in Nebraska.

2. Great Plains Tornado Outbreak: On April 15, 2012, a tornado outbreak occurred in the Great Plains region which includes Nebraska. Over 120 tornadoes were reported in just a few days, with significant damage reported to towns and cities throughout the region.

3. First Native American Bank: On April 15, 1981, the Omaha Nation opened the first Native American-owned bank in the United States. Located in Macy, Nebraska, the bank was a significant achievement for the Omaha Nation and other Native American tribes.

4. Homestead Act: On April 15, 1862, President Abraham Lincoln signed the Homestead Act into law. This provided western settlers, including those in Nebraska, with the opportunity to claim up to 160 acres of land each from the government.

5. Omaha Race Riot: On April 15, 1919, a race riot erupted in Omaha, Nebraska, sparked by a rumor that a young black man had assaulted a white woman. The riot led to the deaths of two black men and the lynching of another. It is considered one of the worst race riots in American history.