1. In 1865, the Idaho Territory was established by an act of Congress, which included present-day Idaho, Montana, and Wyoming. This gave the region greater autonomy and paved the way for eventual statehood.

2. In 1923, the first recorded winter sports events were held in Sun Valley, Idaho. The resort, which was established by the Union Pacific Railroad, became a popular destination for skiing and other winter activities.

3. In 1968, the Idaho State Capitol Building was added to the National Register of Historic Places. Built in 1905, the building underwent extensive renovations in the 2000s to restore its original grandeur.

4. In 1974, Cecil D. Andrus became the first Democrat elected as governor of Idaho since 1960. Andrus would go on to serve as governor for four terms, and was widely regarded as a champion of environmental conservation.

5. In 1996, an avalanche on Galena Summit near Ketchum, Idaho, killed six skiers and injured several others. The tragedy led to increased efforts to improve avalanche safety in the state's backcountry areas.