1. In 1892, Wyoming became the first state in the United States to grant women the right to vote. This historic event took place on September 15, and paved the way for women's suffrage throughout the country.

2. On September 15, 1903, President Theodore Roosevelt visited Wyoming to address a crowd of 25,000 people at the Wyoming State Fair. During his speech, he praised the state for its progressive policies and commitment to conservation.

3. In 1979, the worst rail disaster in Wyoming history occurred on September 15. A train carrying flammable material derailed and caught fire in the town of Rock Springs, killing three people and causing significant damage to the surrounding area.

4. On September 15, 1928, the University of Wyoming played its first football game under the newly built War Memorial Stadium. The Cowboys defeated Montana State 13-6 in front of a crowd of over 9,000 fans.

5. In 1961, the first commercial oil well in Wyoming's Powder River Basin was drilled on September 15. This discovery led to a significant increase in oil production in the state and helped establish Wyoming as a leading energy-producing state in the United States.