Short answers, pulled from the story.
Tennessee earned the nickname during the War of 1812, when 3,500 Tennesseans answered the General Assembly's call to serve. The name was solidified during the Mexican-American War, when President James K. Polk called for 2,800 soldiers from the state and more than 30,000 volunteered.
Tennessee derives its name from Tanasi, a Cherokee town in present-day Monroe County on the river now called the Little Tennessee. Recent research suggests the Cherokees may have adapted the name from the Yuchi word Tana-tsee-dgee, meaning roughly "where the waters meet". The modern spelling was standardized by South Carolina Governor James Glen in the 1750s.
East Tennessee was chosen for uranium enrichment because of abundant TVA electric power, low population density, and inland geography that allowed natural separation of facilities. The planned community of Oak Ridge was built to house workers and equipment, and the Clinton Engineer Works there enriched uranium at three major facilities for use in atomic bombs. After the war, the Oak Ridge National Laboratory became the largest national laboratory in the Department of Energy system.
Memphis is widely regarded as the epicenter of the blues, with musicians including W. C. Handy performing on Beale Street as early as 1909. Sun Records in Memphis is where Elvis Presley, Johnny Cash, Carl Perkins, Jerry Lee Lewis, Roy Orbison, and Charlie Rich all began their recording careers, making it a birthplace of rock and roll in the 1950s. Stax Records, also in Memphis, produced the Memphis soul subgenre in the late 1950s and 1960s.
Tennessee was the last state to secede from the Union, joining the Confederacy in June 1861 after a second referendum passed 69-31%. The state was deeply divided: East Tennessee was largely pro-Union while Middle and West Tennessee supported the Confederacy. Tennessee was also the first former Confederate state readmitted to Congress after the war, on the 24th of July 1866.
The Great Smoky Mountains National Park is located in eastern Tennessee and is the most visited national park in the United States, drawing more than 14 million visitors annually. It is home to more salamander species than anywhere else in the world and anchors a large tourism industry centered on nearby Gatlinburg and Pigeon Forge. Congress authorized its establishment in 1926, and it was officially established in 1934 and dedicated in 1940.