By Don D.Crawford 9-09 citing wikipedia
Meriwether Lewis (August 18, 1774–October 11, 1809) was an American explorer, soldier, and public administrator, best known for his role as the leader of the Lewis and Clark Expedition also known as the Corps of Discovery, with William Clark, whose mission was to explore the territory of the Louisiana Purchase.
Lewis was born in Albemarle County, Virginia, in the present-day community of Ivy. He was the son of Lt. William Lewis of Locust Hill (1733 – November 17, 1779), who was of Welsh ancestry, and Lucy Meriwether (February 4, 1752 – September 8, 1837), daughter of Thomas Meriwether and Elizabeth Thornton. (Thornton was the daughter of Francis Thornton and Mary Taliaferro). He moved with his mother and stepfather Captain John Marks to Georgia in May of 1780. They settled along the Broad River in the Goosepond Community within the Broad River Valley in Wilkes County (now Oglethorpe County).
During his time in Georgia, Lewis enhanced his skills as a hunter and outdoorsman. He would often venture out in the middle of the night in the dead of winter with only his dogs to go hunting. Even at his early age he was interested in natural history, which would develop into a lifelong passion. His mother taught him how to gather wild herbs for medicinal purposes. It was also in the Broad River Valley that Lewis first dealt with a native Indian group. The Cherokee lived in antagonistic proximity to the white settlers, but Lewis seems to have been a champion for them amongst his own people. It was in Georgia that he met Eric Parker, who was the first to introduce him to the idea of traveling. At thirteen, he was sent back to Virginia for education by private tutors. One of these was Parson Matthew Maury, an uncle of Matthew Fontaine Maury. Parson Maury was a son of Charles Goodyear Maury who was Thomas Jefferson's teacher for two years. In 1793, Lewis graduated from Liberty Hall (now Washington and Lee University), joined the Virginia militia, and in 1794 he was sent as part of a detachment involved in putting down the Whiskey Rebellion.
In 1795, he joined the U.S. Army, as a Lieutenant, where he served until 1801, at one point in the detachment of William Clark, who would later become his companion in the Corps of Discovery.
On April 1, 1801, he was appointed as an aide by President Thomas Jefferson, whom he knew personally through Virginia society in Albemarle County. Lewis resided in the presidential mansion, and frequently conversed with various prominent figures in politics, the arts and other circles. Originally, he was to provide information on the politics of the United States Army, which had seen an influx of Federalist officers as a result of John Adams's “midnight appointments.”  When Jefferson began to formulate and to plan for an expedition across the continent, he chose Lewis to lead the expedition.
 Expedition See also: Lewis and Clark Jefferson selected Captain Meriwether Lewis to lead the proposed expedition, afterwards known as the Corps of Discovery. Lewis became intimately involved in planning the expedition and was sent by Jefferson to Philadelphia, Pennsylvania, for additional instruction in cartography and other skills for making scientific observations. In June 1803, Jefferson provided Lewis with basic objectives for the mission, focusing on the exploration of the Missouri river and any related streams which might provide access to the Pacific Ocean.
Lewis suggested that the expedition would benefit from a co-commander and, with Jefferson's consent, offered the assignment to his friend and former commanding officer, William Clark. Clark and Lewis were both relatively young and adventurous and had shared experience as woodsmen-frontiersmen and Army officers. However the two men were quite different in education and temperament. Lewis was introverted and moody while Clark was extroverted, even-tempered and gregarious. Lewis, who had a better education, possessed a philosophical and speculative outlook and was at home with abstract ideas. Clark was more pragmatic and practical. Because of bureaucratic delays in the U.S. Army, Clark officially only held the rank of Second Lieutenant at the time, but Lewis concealed this from expedition members and shared the leadership of the expedition, always referring to Clark as “Captain”.
Lewis departed St. Louis for the Louisiana Purchase—via the Ohio River in the summer of 1803, gathering supplies, equipment, and personnel along the way. Between 1804 and 1806, the Corp of Discovery explored thousands of miles of the Missouri and Columbia River watersheds, searching for an all-water route to the Pacific Ocean. Generally sharing leadership responsibilities with William Clark, although technically the leader, Lewis led the expedition safely across the Rocky Mountains to the Pacific and back, with the loss of just one man, Charles Floyd, who died of apparent appendicitis. In the course of the journey, Lewis observed, collected, and described hundreds of plants and animal species previously unknown to science. The expedition was the first point of Euro-American contact for several Native American tribes; through translators and sign language, Lewis conducted rudimentary ethnographic studies of the peoples he encountered, even as he laid the groundwork for a trade economy to ensure American hegemony over its vast new interior territory.
On August 11, 1806, near the end of the expedition, Lewis was shot in the left thigh by Pierre Cruzatte, a near-blind man under his command, while both were hunting for elk. His wound hampered him for the rest of the journey. At first, Pierre blamed Blackfeet Indians for the injury, but after the Corps found no sign of Indians, he admitted the accident. Clark bandaged and treated Lewis's wound, and the Corps continued the long way back to St. Louis.
 Return and gubernatorial duties After returning from the expedition, Lewis received a reward of 1,600 acres of land. In 1807, Jefferson appointed him governor of the Louisiana Territory; he settled in St. Louis. Lewis was a good administrator, but due to quarreling local political leaders, approval of trading licenses, land grant politics, Indian depredations, and a slow-moving mail system, it appeared that Lewis was a poor administrator who failed to keep in touch with his superiors in Washington.
Lewis was a Freemason, initiated, passed and raised in Door To Virtue Lodge No. 44 in Albemarle, Virginia, between 1796 and 1797. On August 2, 1808, Lewis and several of his acquaintances submitted a petition to the Grand Lodge of Pennsylvania in which they requested a dispensation to establish a lodge in St. Louis. Lewis was nominated and recommended to serve as the first Master of the proposed Lodge, which was warranted as Lodge No. 111 on September 16, 1808.
 Death On September 3, 1809, Lewis set out for Washington D.C. where he hoped to resolve issues regarding the denied payment of drafts he had drawn against the War Department while serving as the first American governor of the Louisiana Territory. Lewis started out with the intention of traveling to Washington by ship from New Orleans but changed his plans while in route down the Mississippi and decided to make an overland journey via the Natchez Trace instead. The Natchez Trace was the old pioneer road between Natchez, Mississippi and Nashville, Tennessee. On October 10, 1809 he stopped at an inn on the Natchez Trace called Grinder's Stand, about 70 miles (110 km) from Nashville, Tennessee. Lewis requested a glass of whiskey almost as soon as he climbed down from his horse. After he excused himself from dinner, he went to his bedroom. In the predawn hours of October 11, the innkeeper heard gunshots. Servants found Lewis badly injured from multiple gunshot wounds. He died shortly after sunrise.
While modern historians generally accept his death as a suicide, there is some debate. Mrs. Grinder, the tavern-keeper's wife, claimed Lewis acted strangely the night before his death. She said that during dinner Lewis stood and paced about the room talking to himself in the way one would speak to a lawyer. She observed his face to flush as if it had come on him in a fit. After he retired for the evening, Mrs. Grinder continued to hear him talking to himself. At some point in the night she heard multiple gunshots, and what she believed was someone asking for help. She claimed to be able to see Lewis through the slit in the door crawling back to his room. She never explained why, at the time, she didn't investigate further concerning Lewis's condition or the source of the gunshots. The next morning, she sent for Lewis's servants, who found him weltering in his blood but alive for several hours.
When Clark and Jefferson were informed of Lewis' death, both accepted it as suicide, but his family contended it was murder. In later years a court of inquiry explored whether they could charge the tavern-keeper with Lewis' death. They dropped the inquiry for lack of evidence or motive.
The explorer was buried near present day Hohenwald, Tennessee, not far from where he died. The State of Tennessee erected a monument over his grave in 1843. The Tennessee State Commission charged with locating the grave and erecting the monument wrote in its official report that it was likely Lewis died at the hands of an assassin. Today, the grave site is maintained by the Natchez Trace Parkway. During a ceremony at Lewis' grave on Oct. 7, 2009, marking the 200th anniversary of his death, a bronze bust of Lewis will be dedicated to the Natchez Trace Parkway for a planned visitor center at the grave site area. The event will also serve as the first national memorial service to Lewis, who was not given the honor of a funeral or a memorial service at the time of his death. The Meriwether Lewis Chapter of the Lewis and Clark Trail Heritage Foundation will host the event, called “Courage Undaunted—The Final Journey.”
 Legacy Lewis never married. Although he died without legitimate heirs, he does have the putative DNA model haplotype for his paternal ancestors' lineage, which was that of the Warner Hall. He was also related to Robert E. Lee and Elizabeth II of the United Kingdom, among others. He was related to George Washington by marriage: his first cousin once removed was Fielding Lewis, Washington's brother-in-law. He was also a second cousin once removed of Washington's on his father's side.
For many years, Lewis' legacy was overlooked, inaccurately assessed, and even tarnished by his alleged suicide. Yet his contributions to science, the exploration of the Western U.S., and the lore of great world explorers, are considered incalculable.
Four years after Lewis' death, Thomas Jefferson wrote:
Of courage undaunted, possessing a firmness and perseverance of purpose which nothing but impossibilities could divert from its direction, … honest, disinterested, liberal, of sound understanding and a fidelity to truth so scrupulous that whatever he should report would be as certain as if seen by ourselves, with all these qualifications as if selected and implanted by nature in one body for this express purpose, I could have no hesitation in confiding the enterprise to him.
Jefferson also stated that Lewis had a “luminous and discriminating intellect.”
The alpine plant Lewisia (family Portulacaceae), popular in rock gardens, is named after Lewis, as is Lewis's Woodpecker. Geographic names that honor him include Lewis County, Idaho,Lewis County, Kentucky; Lewis County, Tennessee; Lewisburg, Tennessee; Lewiston, Idaho; Lewis County, Washington; the U.S. Army fort Fort Lewis, Washington, the home of the US Army 1st Corps (I Corps), and especially Lewis and Clark County, Montana, the home of the capital city, Helena. A day use campground at Gates of the Mountains Wilderness, north of Helena, Meriwether Picnic site. A cave, Lewis and Clark Caverns between Three Forks and Whitehall, Montana. The US Navy Polaris nuclear submarine USS Lewis and Clark was named for him and William Clark.