1. Missouri celebrates its birthday on February 15 as it was admitted to the Union on this day in 1821. The state was originally part of the Louisiana Territory and was named after the Missouri River.

2. In 1864, the Battle of Nashville in the American Civil War ended, and Missouri troops played a significant role in the Union victory. The Missouri soldiers fought bravely alongside other Union forces and helped to further weaken the Confederacy in the South.

3. On February 15, 1888, St. Louis experienced one of the deadliest tornadoes in American history. The tornado killed 255 people, injured over a thousand more, and caused significant damage to the city. The tornado led to increased safety measures in the area and contributed to the development of modern meteorology.

4. The Missouri State Capitol building in Jefferson City was destroyed by fire on February 15, 1911. The fire was caused by faulty wiring and quickly spread throughout the building, causing extensive damage. A new Capitol building was constructed and opened in 1917 to replace the destroyed structure.

5. In 1965, the Gateway Arch in St. Louis was completed on February 15 after two and a half years of construction. The arch is a symbol of St. Louis and its role as the "Gateway to the West". The arch is the tallest man-made monument in the Western Hemisphere and attracts millions of visitors each year.