1. On September 4, 1835, the Treaty of Traverse des Sioux was signed between the United States government and the Dakota (Sioux) tribe, which ceded most of their land in Iowa and Minnesota to the government.

2. In 1899, on September 4, the African American Congress of Iowa was held in Des Moines, marking an important moment in the fight for Civil Rights in the state.

3. September 4, 1918, saw the activation of Camp Dodge in Polk County, Iowa, which trained and mobilized soldiers during World War I.

4. On September 4, 1945, Iowa State College (now Iowa State University) was designated as the site for the federal government's Ames Laboratory, which conducts cutting-edge research in materials science, energy, and related fields.

5. In 2008, on September 4, Senator Tom Harkin of Iowa delivered a speech at the Democratic National Convention in which he extolled the virtues of his home state and called for greater investment in education, healthcare, and social welfare programs.