1. In 1954, Elvis Presley had his first professional recording session at Sun Studio in Memphis, Tennessee. He recorded the songs "That's All Right" and "Blue Moon of Kentucky," which would later become hits and solidify his place in rock and roll history.

2. On July 21, 1861, the First Battle of Manassas took place in Virginia during the American Civil War. Tennessee played a significant role in the battle, with multiple regiments from the state participating on both sides. The Confederates ultimately won the battle, leading to a surge in Southern morale.

3. The first public library in Tennessee was established in Nashville on July 21, 1899. It was located in the city's former post office building and was considered a significant step forward in promoting education and literacy in the state.

4. In 1953, the Tennessee Valley Authority (TVA) began construction on the Chickamauga Dam on the Tennessee River. The dam was designed to help control flooding and generate hydroelectric power, ultimately benefiting the region's economy and infrastructure.

5. On July 21, 1977, country music star Waylon Jennings performed at the Starwood Amphitheater in Nashville. The concert was notable because it was the first time a country artist had headlined a show at the venue, which had previously only hosted rock acts. The show was a success and helped to further legitimize country music as a mainstream genre.