1. Idaho Statehood: On September 4, 1890, Idaho became the 43rd state of the US, following a vote by Congress allowing the territory to become a state.

2. Potlatch, Idaho: The town of Potlatch, Idaho, was established on September 4, 1905. The town was named after a traditional Native American feast, which was common among the indigenous people of the region.

3. The Borah Peak Earthquake: On September 4, 1983, the largest recorded earthquake in Idaho's history occurred. The earthquake measured 6.9 on the Richter scale and caused significant damage and multiple fatalities.

4. Craters of the Moon National Monument: On September 4, 1924, Craters of the Moon National Monument was established. The park covers over 750,000 acres of volcanic rocks and is a popular destination for hikers, photographers, and nature enthusiasts.

5. Woman Suffrage: Idaho was one of the first states to grant women the right to vote. Governor John Nugent signed the bill into law on February 19, 1896, and on September 4 of the same year, women were allowed to vote in Idaho for the first time in a general election.