Native American inhabitants
The area now known as Tennessee was first settled by Paleo-Indians nearly 11,000 years ago. The names of the cultural groups that inhabited the area between first settlement and the time of European contact are unknown, but several distinct cultural phases have been named by archaeologists, including Archaic, Woodland, and Mississippian whose chiefdoms were the cultural predecessors of the Muscogee people who inhabited the Tennessee River Valley prior to Cherokee migration into the river's headwaters.

When Spanish explorers first visited Tennessee, led by Hernando de Soto in 1539–43, it was inhabited by tribes of Muscogee and Yuchi people. Possibly because of European diseases devastating the Native tribes, which would have left a population vacuum, and also from expanding European settlement in the north, the Cherokee moved south from the area now called Virginia. As European colonists spread into the area, the native populations were forcibly displaced to the south and west, including all Muscogee and Yuchi peoples, the Chickasaw, and Choctaw. From 1838 to 1839, nearly 17,000 Cherokees were forced to march from "emigration depots" in Eastern Tennessee, such as Fort Cass, to Indian Territory west of Arkansas. This came to be known as the Trail of Tears, as an estimated 4,000 Cherokees died along the way.

Colonial settlement
 
The Transylvania Purchase at Sycamore Shoals in Elizabethton and the Wilderness Road into Kentucky.In 1759, a young James Robertson accompanied explorer Daniel Boone on his third expedition to lands beyond the Alleghany Mountains. The party discovered the "Old Fields" (lands previously cultivated by generations of Native Americans) along the Watauga River valley at present day Elizabethton, in which Robertson planted with corn while Boone continued on to Kentucky. By 1769 Daniel Boone had formed an association with North Carolina promoter and judge Richard Henderson with a goal to purchase and settle a vast tract of Cherokee lands in present day Middle Tennessee and Kentucky, and Boone later relocated his family to the Watuaga Settlement sometime during the Spring of 1771.[14]

James Robertson later returned to North Carolina, and there married Charlotte Reeves in 1767. After the Battle of Alamance in 1771, many North Carolinians refused to take the new oath of allegiance to the Royal Crown and withdrew from the province. Instead of taking their new oath of allegiance, James Robertson led a group of some twelve or thirteen families involved with the Regulator movement from near where present day Raleigh, North Carolina now stands. In 1772, Robertson and the pioneers who had settled in Northeast Tennessee (along the Watauga River, the Doe River, the Holston River, and the Nolichucky River met at Sycamore Shoals to establish an independent regional government known as the Watauga Association.

However, in 1772, surveyors placed the land officially within the domain of the Cherokee tribe, who required negotiation of a lease with the settlers. Tragedy struck as the lease was being celebrated, when a Cherokee warrior was murdered by a white man. Robertson's skillful diplomacy made peace with the irate Native Americans, who threatened to expel the settlers by force if necessary.

All of present day Tennessee was once recognized as one single North Carolina county: Washington County, North Carolina. Created in 1777 from the western areas of Burke and Wilkes Counties, North Carolina, Washington County had as a precursor a Washington District of 1775-76, which was the first political entity named for the Commander-in-Chief of American forces in the Revolution.

Previously named as Tiptonville of Wayne County within the "lost" State of Franklin (along with present day Johnson County, Tennessee; 1785–86)[16], Carter County is named in honor of Landon Carter, Chairman of the Court as defined by the articles of the Watauga Petition and Speaker of the defunct Franklin Senate. Elizabethton is the county seat and was renamed for Landon's wife, Elizabeth MacLin Carter, as well as Elizabeth McNabb, the wife of David McNabb who, with Landon, were members of a committee appointed by the Tennessee Assembly in 1796 to locate and name the county seat of Carter County.

Landon Carter was the son of early Carter County settler, John Carter. John Carter's circa 1780 home known as the Carter Mansion still serves as a tourist attraction. The oldest frame house in Tennessee, this former frontier plantation home is located on the Broad Street Extension on the eastern side of town above the banks of the Watauga River. A landscape painting of a Virginia plantation that was discovered underneath ancient layers of paint covering the wall surface above a fireplace mantle suggest that John Carter may have possibly been an illegitimate son of the wealthy Virginia plantation owner Robert "King" Carter and half-brother to Virignia plantation owner Landon Carter.

American Revolution
 
Daniel Boone Escorting Settlers through the Cumberland Gap (George Caleb Bingham, oil on canvas, 1851–52)Elizabethton (at Sycamore Shoals) was also the Fort Watauga site of the Transylvania Purchase. In March 1775, land speculator and North Carolina judge Richard Henderson met with more than 1,200 Cherokees at Sycamore Shoals, including Cherokee leaders such as Attacullaculla, Oconostota, and Dragging Canoe. In the Treaty of Sycamore Shoals (also known as the Treaty of Watauga), Henderson purchased all the land lying between the Cumberland River, the Cumberland Mountains, and the Kentucky River, and situated south of the Ohio River. The land thus delineated, 20 million acres (81000 km?), encompassed an area half as large as the present state of Kentucky. Henderson's purchase was in violation of North Carolina and Virginia law, as well as the Royal Proclamation of 1763, which prohibited private purchase of American Indian land. Henderson may have mistakenly believed that a newer British legal opinion had made such land purchases legal.

Before the Sycamore Shoals treaty, Henderson had hired Daniel Boone, an experienced hunter who had explored Kentucky, to travel to the Cherokee towns and inform them of the upcoming negotiations. Afterwards, Boone was hired to blaze what became known as the Wilderness Road, which went through the Cumberland Gap and into central Kentucky. Along with a party of about thirty workers, Boone marked a path to the Kentucky River, where he established Boonesborough (near present-day Lexington, Kentucky), which was intended to be the capital of Transylvania. Other settlements, notably Harrodsburg, were also established at this time. Many of these settlers had come to Kentucky on their own initiative, and did not recognize Transylvania's authority. A Daniel Boone Trail historical marker is found just outside the downtown Elizabethton business district.

Early during the American Revolutionary War, Fort Watauga at Sycamore Shoals was the attacked in 1776 by Dragging Canoe and his warring faction of Cherokee opposed to the Transylvania Purchase (also referred by settlers as the Chickamauga), and the surviving frontier fort on the banks of the Watauga River.

The Battle of King's Mountain. October 7, 1780.The Overmountain Men serving under Col. Issac Shelby (who years earlier worked as a surveyor for the Transylvania Company) and other Patriot forces engaged and defeated a larger force of British Loyalists at the Battle of Musgrove Mill near present day Clinton, South Carolina. Fort Watauga later served as the September 26, 1780[18] staging area for a much larger contingent of some 1,100 Overmountain Men who were preparing to trek over the Blue Ridge Mountains at Roan Mountain (Roan Highlands) to both engage, and later defeat, the British Army Loyalist forces and later at the Battle of Kings Mountain in North Carolina.

Prior to the American Revolutionary War very little gunpowder had been made in the United States; and, as a British Colony, most had been imported from Britain.[19][page needed] In October 1777, the British Parliament banned the importation of gunpowder into America. Five hundred pounds of black powder was manufactured for the Overmountain Men by Mary Patton and her husband at their Gap Creek powder mill, and the Overmountain Men stored the Patton black powder on that first rainy night in a dry cave known as Shelving Rock that is located nearby the Roan Mountain State Park at present day Roan Mountain, Tennessee.[18] During January 1781, the Overmountain Men also fought the British at the Battle of Cowpens in South Carolina.

U.S. Civil War
 

Samuel P. CarterOn the recommendation of Military Governor of Tennessee Andrew Johnson, U.S. naval officer Samuel Powhattan (S.P.) Carter was promoted to the brevet rank of brigadier general and assigned by U.S. President Abraham Lincoln to engage cavalry based in Kentucky against Confederate held railroad lines and bridges in Tennessee during the Civil War.

In early 1861, after receiving a letter from Carter assuring his loyalty to the Union should a civil war break out, Tennessee Governor Andrew Johnson used his influence in the United States Department of War for Carter to organize and train militia within East Tennessee. After leading successful cavalry operations at the Battle of Mill Springs on January 19, 1862, Carter accepted a commission as Brigadier General of volunteers in May and later continued leading operations at the Battle of Cumberland Gap in June as well as raids against Holston, Carter's Station, and Jonesville in December, in support of General William S. Rosecrans' attack on Murfreesboro.

In July 1863, Carter was placed in command of the XXIII Corps cavalry division and would continue campaigning across Tennessee throughout the year. By 1865, Carter was in North Carolina and commanding the left wing of the Union forces at the Battle of Kingston. He was promoted to Brevet Major General of Volunteers, briefly commanding the XXIII Corps before being mustered out of volunteer service in January 1866.

While Carter was serving in the Union Army, the U.S. Navy promoted him to lieutenant commander in 1863, then to commander in 1865. A Tennessee Historical Marker located on West Elk Avenue in front of the S.P. Carter Mansion in downtown Elizabethton, Tennessee commemorates his life and naval career.

The Veterans' Monument in downtown Elizabethton was originally dedicated in 1904 to both Union and Confederate veterans from Carter County. It is in the form of an obelisk, constructed primarily from river rock collected from the nearby Doe River, guarded by two short Civil War field cannon.

Railroad history
During the early 20th century, Elizabethton became a rail hub, served by three different railroad companies.

Beginning in the 1880s, the narrow gauge engine known as the "Tweetsie" ran on East Tennessee and Western North Carolina Railroad (a.k.a. the 'ET&WNC ) between Johnson City and passing through Elizabethton before climbing into the Blue Ridge Mountains, eventually connecting to Boone, North Carolina in 1916.

In 1927, the 9-mile (14 km) portion of the ET&WNC railroad from Johnson City to Elizabethton was converted to standard gauge in order to more efficiently serve the NARC and Bemberg Rayon Plants.

The narrow gauge portion of the ET&WNC ceased operations in 1950 and was subsequently abandoned, however the standard gauge portion of the line from Johnson City to Elizabethton continued to operate until 2003 as the East Tennessee Railway. Today the railroad's dormant track remains in place, though its future is uncertain.

One of the ET&WNC's narrow gauge steam locomotives (Engine #12) is still in existence, operating at the "Tweetsie Railroad" theme park at nearby Boone, North Carolina.

The Southern Railway operated a branch line into Elizabethton until the flood of 1940. It connected with the ET&WNC at a small railroad yard near the confluence of the Watauga River and the Doe River.

In the 1910s and 1920s, another small railroad, The Laurel Fork Railway, operated out of Elizabethton paralleling the ET&WNC and Doe River to Hampton, Tennessee. At Hampton the line split off and ran to a sawmill near present-day Watauga Lake.