[2] The county is named in honor of Simón Bolívar, early 19th-century leader of the liberation of several South American territories from Spain.

The Cleveland, Mississippi, Micropolitan Statistical Area includes all of Bolivar County.

Large industrial-scale agricultural operations have reduced the number of farm workers needed, and the population is half of its peak in 1930.

This number only increased, because around 1860, the population was about 87% slaves, due to its mostly agricultural economy, and continued to gain a high black population, relating to it being in the delta,[3] and mound bayou's[clarify] pressure for African-Americans to move to the delta.

[4] In the 1920s, Bolivar county was a hotspot for UNIA chapters, with 17 chapters, and by 1960, it had a significant local civil rights movement, and remains a mostly black area today.

As of the 2020 United States Census, there were 30,985 people, 12,114 households, and 7,719 families residing in the county.

25.30% of all households were made up of individuals, and 9.90% had someone living alone who was 65 years of age or older.

[13] Senators Robert F. Kennedy and Joseph S. Clark, Jr. had visited "pockets of poverty" in the Mississippi Delta 40 years earlier.

In Cleveland, they observed barefoot, underfed African-American children in tattered clothing, with vacant expressions and distended bellies.

[21] As recently as the 1960s the school board of Bolivar County censored what black children were allowed to learn, and mandated that "Neither foreign languages nor civics shall be taught in Negro schools.