1. Idaho Statehood: On May 4, 1890, Idaho formally became the 43rd state in the United States after President Benjamin Harrison signed a proclamation declaring its admission to the Union. Idaho residents celebrate May 4th as Idaho Statehood Day.

2. 1925 Anderson Fire: On May 4, 1925, the Anderson Fire broke out in a dry forest near the town of St. Maries, Idaho. In just two days, the fire burned over 100,000 acres of land, destroyed homes and towns, and claimed the lives of eight firefighters. The devastating wildfire prompted the U.S. Forest Service to implement new firefighting techniques and invest in fire prevention efforts.

3. Pocatello Riot: May 4, 1991, marked the beginning of the Pocatello Riot, a three-day-long disturbance that erupted in the streets of Pocatello, Idaho, following a racially charged incident at a local high school. The riots resulted in several arrests and injuries, and prompted the city and state to re-examine issues of racism and inequality.

4. Earnest Hemingway: On May 4, 1899, renowned author and journalist Ernest Hemingway was born in Oak Park, Illinois. Although he did not have direct ties to Idaho, Hemingway spent several summers in Sun Valley, where he wrote many of his most famous works, such as "For Whom the Bell Tolls" and "The Sun Also Rises."

5. Boise State University: May 4, 1965, marks the founding of Boise State University, one of the largest universities in Idaho. The university began as a junior college with just 57 students, but has since grown to over 25,000 students and offers a diverse range of academic programs, including business, engineering, and nursing. Boise State is also well-known for its successful football program, which has won several conference championships and NCAA bowl games.