1. Wyoming was still a territory when October 31, 1864, occurred. On that day, the area now known as Wyoming was part of the larger Dakota Territory. It wasn't until 1868 that Wyoming was created as an independent territory.

2. On October 31, 1890, Wyoming became the 44th state in the United States. This happened just a few days after the majority of the territory's residents voted in favor of a new constitution that would allow for statehood. Wyoming was the first state to give women the right to vote.

3. The infamous outlaw Butch Cassidy spent time in Wyoming during his criminal career. According to legend, Cassidy robbed the Union Pacific train near Wilcox, Wyoming on October 31, 1899. This event is often referred to as the Wilcox Train Robbery.

4. During World War II, Wyoming was home to several prisoner of war camps. These camps held Italian and German prisoners captured during the fighting in North Africa and Italy. On October 31, 1943, an Italian prisoner at one of Wyoming's camps died by suicide.

5. In 1978, a devastating blizzard hit the state of Wyoming on Halloween night. The storm caused widespread power outages and left many residents stranded in their homes. Some areas received up to 30 inches of snow, and several people died as a result of the storm. This event is still remembered as one of the most severe blizzards in the state's history.