1. Nebraska became a state: On December 15, 1866, Nebraska officially became the 37th state in the United States of America.

2. Nebraska territory established: On December 15, 1854, President Franklin Pierce signed the Kansas-Nebraska Act, creating the Nebraska Territory.

3. First airplane flight: On December 15, 1917, the first airplane flight took place in Lincoln, Nebraska. The pilot was a Nebraska native named Art Smith.

4. Nebraska's first radio station: On December 15, 1921, Nebraska's first radio station, KFKX, began broadcasting in Hastings, Nebraska.

5. Interstate 80 completed: On December 15, 1972, the final stretch of Interstate 80 was completed in Nebraska, allowing for easier travel across the state and connecting it with the rest of the country.