1. Statehood Day: September 15 marks Statehood Day in Nebraska, commemorating the day in 1867 when the state officially joined the Union as the 37th state.

2. Arbor Day: Nebraska is known as the birthplace of Arbor Day, and on September 15, 1872, the state held the first-ever Arbor Day celebration in the town of Nebraska City. Today, Arbor Day is celebrated worldwide on the last Friday in April.

3. Pioneer-Spirit Statue: On September 15, 1932, the Pioneer-Spirit statue was unveiled in Kearney. The 16-foot bronze statue by artist John David Brcin symbolizes the spirit of western pioneers and their determination to settle the plains.

4. Bob Devaney: Legendary Nebraska football coach Bob Devaney was born on September 15, 1915. Devaney coached the Cornhuskers from 1962 to 1972, during which time he won two national championships and compiled a record of 101-20-2.

5. Lewis and Clark: On September 15, 1804, the Lewis and Clark Expedition passed through what is now Nebraska. The explorers traveled up the Missouri River and camped near present-day Omaha, documenting their encounters with native peoples and the flora and fauna of the region.