The name is a simplification of "King's Port", originally referring to the area on the Holston River known as King's Boat Yard, the head of navigation for the Tennessee Valley. Kingsport is the largest city in the Kingsport–Bristol–Bristol, TN-VA Metropolitan Statistical Area (MSA), which had a population of 309,544 as of 2010. The Metropolitan Statistical Area is a component of the Johnson City–Kingsport–Bristol, TN-VA Combined Statistical Area – commonly known as the "Tri-Cities" region. Census data from 2006–2008 for the Tri-Cities Combined Statistical Area estimates a population of 496,454. Kingsport is commonly included in what is known as the Mountain Empire, which spans a portion of southwest Virginia and the mountainous counties in Tennessee to the east.
The North and South Forks of the Holston River converge on the west end of what is now Kingsport, and the town itself was known in 1787 as "Salt Lick" along the banks of the South Fork, about a mile from the confluence. The Long Island of the Holston River is near the confluence, which is mostly within the corporate boundaries of Kingsport. The island was an important site for the Cherokee, colonial pioneers and early settlers. Early settlements at the site were used as a staging ground for people taking the Wilderness Road leading to Kentucky through Cumberland Gap. First chartered in 1822, Kingsport became an important shipping port on the Holston River. Goods originating for many miles from the surrounding countryside were loaded onto barges for the journey downriver to the Tennessee River at Knoxville.
In the Battle of Kingsport (December 13, 1864) during the American Civil War, a force of 300 Confederates under Colonel Richard Morgan (1836–1918) stopped a larger Union force for nearly two days. An army of over 5,500 troops under command of Major General George Stoneman (1822–1894) had left Knoxville, Tennessee, to raid Confederate targets in Virginia: the salt works at Saltville, the lead works at Wytheville and the iron works in Marion. While Col. Morgan's small band held off a main Union force under Major General Cullem Gillem on the opposite side the Holston River, Col. Samuel Patton took a force of cavalry to a ford in the river north and came down behind the Confederates. Out-numbered, out-flanked and demoralised by the bitter winter weather, Col. Morgan surrendered. The Confederates suffered 18 dead, and 84 prisoners of war were sent to a Union prison in Knoxville.
The young town lost its charter after a downturn in its fortunes precipitated by the Civil War.
On September 12, 1916, Kingsport residents demanded the death of circus elephant Mary (an Asian elephant who performed in the Sparks World Famous Shows Circus) for her killing of city hotel worker Walter Eldridge, who was hired the day before as an assistant elephant trainer by the circus. Eldridge was killed by Mary in Kingsport while he was taking her to a nearby pond. Mary was impounded by the local sheriff, and the leaders of several nearby towns threatened not to allow the circus to visit if Mary was included. The circus owner, Charlie Sparks, reluctantly decided that the only way to quickly resolve the situation was to hold a public execution. On the following day, she was transported by rail to Erwin, Tennessee, where a crowd of over 2,500 people assembled in the Clinchfield Railroad yard to watch her hang from a railroad crane.
Re-chartered in 1917, Kingsport was an early example of a "garden city", designed by city planner and landscape architect John Nolen of Cambridge, Massachusetts. It carries the nickname the Model City from this plan, which organized the town into areas for commerce, churches, housing and industry. The result included some of the earlier uses of traffic circles (roundabouts) in the United States. Kingsport was among the first municipalities with a city manager form of government and a school system built on a model developed at Columbia University. Most of the land on the river was devoted to industry. Indeed, most of The Long Island is now occupied by Eastman Chemical Company, which is headquartered in Kingsport.
Pal's Sudden Service, a regional fast-food restaurant chain, opened its first location in Kingsport in 1956.