[4] In 1834–1835, Little River became part of Robertson's Colony, made up of settlers from Nashville, Tennessee, led by Sterling C. Robertson; they were the families of Captain Goldsby Childers, Robert Davison, John Fulcher, Moses Griffin, John Needham, Michael Reed and his son William Whitaker Reed, William Taylor, and Judge Orville T.

[5] The next year, the Republic of Texas founded Baylor Female College (since developed as University of Mary Hardin–Baylor).

[5] During the early years of the Reconstruction era (1865–1877), so much violence occurred in the county that the government stationed federal troops in Belton.

As in many areas, a local version of white paramilitary insurgents developed who were similar to the Ku Klux Klan; they worked to suppress black and Republican voting.

In 1881, the Gulf, Colorado and Santa Fe Railway, the first railroad to be built in Bell County, established Temple as its headquarters.

[10] As another improvement, in 1905, the Belton and Temple Interurban electric railway was completed, providing service between the cities.

In many areas, it was concentrated on nativist issues, opposing Catholic and Jewish immigration from eastern and southern Europe.

After a scandal involving the leader of the KKK, the group's influence declined markedly by the end of the decade.

In 1954, the U.S. Supreme Court ruled in Brown v. Board of Education that racial segregation in public schools, supported by all the taxpayers, was unconstitutional.

[15] On June 21st, 1999, Brandon Bernard and four accomplices kidnapped and murdered youth pastors Todd and Stacie Bagley near Killeen, Texas.

[16] In the 2009 Fort Hood shooting, Army major Nidal Hasan murdered 13 people and wounded 30 others before being paralyzed in return fire.

[17] In the 2014 Fort Hood shootings, Army Specialist Ivan Lopez murdered three people and wounded 16 others.

[18] On May 3, 2022, a stabbing at Belton High School by a fellow student left 18-year-old Jose Luis "Joe" Ramirez Jr. critically injured.

[19] On December 21, 2024, John Darrel Schultz, 53, drove a pickup truck through the outside entrance of the JCPenney store at the Killeen Mall during a police chase, striking five people inside before being fatally shot by officers.

The racial makeup of the county was 61.4% White, 21.5% Black, 0.8% Native American, 2.8% Asian, 0.8% Pacific Islander, and 5.0% from two or more races.

About 21.6% of the population was Hispanic or Latino of any race; 14.9% were of Mexican, 3.6% were of Puerto Rican, 0.2% Cuban, and 0.2% were of Dominican descent.

These major highways run through Bell County: The Hill Country Transit District operates a regularly scheduled fixed-route bus service within the urban areas of Killeen and Temple, as well as a paratransit service throughout the county.

In 1952 and 1956, Republican Dwight D. Eisenhower (who was born in Texas) won the state while losing Bell County.

Democratic strength in the county is concentrated in the city of Killeen, which gave Joe Biden 63.4% of the vote in the 2020 election.