This article is about the United States president. For other uses, see Thomas Jefferson (disambiguation).
3rd President of the United States
In officeMarch 4, 1801 – March 4, 1809
Aaron BurrGeorge Clinton
2nd Vice President of the United States
In officeMarch 4, 1797 – March 4, 1801
1st United States Secretary of State
In officeMarch 22, 1790 – December 31, 1793
John Jay (Acting)
United States Ambassador to France
In officeMay 17, 1785 – September 26, 1789
Congress of the Confederation
Delegate from Virginia to theCongress of the Confederation
In officeNovember 1, 1783 – May 7, 1784
Richard Henry Lee
2nd Governor of Virginia
In officeJune 1, 1779 – June 3, 1781
Delegate from Virginia to theSecond Continental Congress
In officeJune 20, 1775 – September 26, 1776
April 13, 1743Shadwell, Colony of Virginia
July 4, 1826 (aged 83)Charlottesville, Virginia
Martha Wayles Skelton
College of William and Mary
Classic engraving of Jefferson
1st Presidential Commemorative of 1904.
Thomas Jefferson (April 13, 1743 – July 4, 1826) was the third President of the United States (1801–1809) and the principal author of the Declaration of Independence (1776). An influential Founding Father, Jefferson envisioned America as a great "Empire of Liberty" that would promote republicanism.
Jefferson served as the wartime Governor of Virginia (1779–1781), barely escaping capture by the British in 1781.  Many people were not pleased with his tenure and in the next election he did not win office again in Virginia.  From mid-1784 through late 1789 Jefferson lived outside the United States. He served in Paris initially as a commissioner to help negotiate commercial treaties. In May 1785 he succeeded Benjamin Franklin as the U.S. Minister to France.
He was the first United States Secretary of State (1789–1793) under George Washington and advised him against a national bank and the Jay Treaty. He was the second Vice President (1797–1801) under John Adams. Winning on an anti-federalist platform, Jefferson took the oath of office and became President of the United States in 1801. As president he negotiated theLouisiana Purchase (1803), and sent the Lewis and Clark Expedition (1804–1806) to explore the vast new territory and lands further west. Jefferson always distrusted Britain as a threat to American security; he rejected a renewal of the Jay Treaty that his ambassadors had negotiated in 1806 with Britain and promoted aggressive action, such as the embargo laws, that contributed to the already escalating tensions with Britain and France leading to war with Britain in 1812 after he left office.
Jefferson idealized the independent yeoman farmer as exemplar of republican virtues, distrusted cities and financiers, and favored states' rights and a limited federal government. Jefferson supported the separation of church and state and was the author of the Virginia Statute for Religious Freedom (1779, 1786). Jefferson's revolutionary view on individual religious freedom and protection from government authority have generated much interest with modern scholars. He was the eponym of Jeffersonian democracy and the co-founder and leader of the Democratic-Republican Party, which dominated American politics for 25 years.
Born into a prominent planter family, Jefferson owned hundreds of slaves throughout his life; he held views on the racial inferiority of Africans common for this period in time. While historians long discounted accounts that Jefferson had an intimate relationship with his slaveSally Hemings, it is now widely held that he did and had six children by her.
Jefferson was a polymath who spoke five languages and could read two others. He was a major book collector with an enormous library, much of which he sold to the Library of Congress in 1814 after the British set fire to the Capitol which destroyed most of its works. He wrote more than sixteen thousand letters and was acquainted with nearly every influential person in America, and many throughout Europe. Jefferson is constantly rated by historical scholars as one of the greatest U.S. presidents.
1 Early life and education
2 Marriage and family
2.1 Wife and children
3 Political career from 1775 to 1800
3.1 Drafting a declaration
3.2 State legislator
3.3 Governor of Virginia
3.4 Notes on the State of Virginia
3.5 Member of Congress
3.6 Minister to France
3.7 Secretary of State
3.8 Break from office
3.9 Election of 1796 and Vice Presidency
3.10 Election of 1800
4 Presidency 1801–1809
4.1 Administration, Cabinet and Supreme Court appointments
4.2 First Barbary War
4.3 Louisiana Purchase
4.4 Lewis and Clark Expedition
4.5 West Point
4.6 Other involvements
4.7 Second Term
5 Father of a university
6.1 Views of slaves and blacks
7 Life as a widower
7.1 Sally Hemings and her children
8 Interests, activities, inventions, and improvements
9 Political philosophy and views
11 Native American policy
11.1 Acculturation and assimilation
11.2 Forced Indian relocation
13 Reputation and memorials
15 See also
17.2 Politics and ideas
17.4 Legacy and historiography
17.5 Primary sources
18 External links
Early life and education
Main article: Ancestry of Thomas Jefferson
The third of ten children, Thomas Jefferson was born on April 13, 1743 into the Randolph family that linked him to some of the most prominent individuals in Virginia. His mother was Jane Randolph, daughter of Isham Randolph of Dungeness, a ship's captain and sometime planter, first cousin to Peyton Randolph, and granddaughter of wealthy English and Scottish gentry. Jefferson's father was Peter Jefferson, a planter and surveyor in Albemarle County (Shadwell, then Edge Hill, Virginia.) He was of possible Welsh descent, although this remains unclear. When Colonel William Randolph, an old friend of Peter Jefferson, died in 1745, Peter assumed executorship and personal charge of William Randolph's estate in Tuckahoe as well as his infant son, Thomas Mann Randolph, Jr. That year the Jeffersons relocated to Tuckahoe, where they would remain for the next seven years before returning to their home in Albemarle in 1752. Peter Jefferson was appointed to the colone]cy of the county, an important position at the time.
When Thomas Jefferson was 22, his oldest sister Jane died at the age of 25 on October 1, 1765. He fell into a period of deep mourning, as he was already saddened by the absence of his sisters Mary, who had been married several years to Thomas Bolling, and Martha, who had wed in July to Dabney Carr. Both had moved to their husbands' residences. Only Jefferson's younger siblings Elizabeth, Lucy, and the two toddlers, were at home. He drew little comfort from the younger ones, as they did not provide him with the same intellectual stimulation as the older sisters had.
In 1752, Jefferson began attending a local school run by a Scottish Presbyterian minister. At the age of nine, Jefferson began studying Latin,Greek, and French; he learned to ride horses, and began to appreciate the study of nature. He studied under the Reverend James Maury from 1758 to 1760 near Gordonsville, Virginia. While boarding with Maury's family, he studied history, science and the classics.
At age 16, Jefferson entered the College of William & Mary in Williamsburg, and first met the law professor George Wythe, who became his influential mentor. For two years he studied mathematics, metaphysics, and philosophy under Professor William Small, who introduced the enthusiastic Jefferson to the writings of the British Empiricists, including John Locke, Francis Bacon, and Isaac Newton. He also improved his French, Greek, and violin. A diligent student, Jefferson displayed an avid curiosity in all fields and graduated in 1762 with highest honors.
He read law while working as a law clerk for Wythe. They also read a wide variety of English classics and political works. Jefferson was admitted to the Virginia bar five years later in 1767.
Throughout his life, books played a vital role in Jefferson's education. Even during the American Revolution and while minister to France, Jefferson collected and accumulated thousands of books for his library at Monticello. A significant portion of Jefferson's library was also bequeathed to him in the will of George Wythe who himself had an extensive library. Always eager for more knowledge, Jefferson's education would continue throughout most of his life. Jefferson once stated "I cannot live without books".
Jefferson handled many cases as a lawyer in colonial Virginia, and was very active from 1768 to 1773. Jefferson's client list included members of the Virginia's elite families, including members of his mother's family, the Randolphs.
In 1768 Thomas Jefferson started the construction of Monticello, a neoclassical mansion. Since childhood, Jefferson had always wanted to build a beautiful mountaintop home within sight of Shadwell. Jefferson fell greatly in debt by spending lavishly over the years on Monticello in what was a continuing project to create a neoclassical environment, based on his study of the architect Andrea Palladio and the classical orders. 
Besides practicing law, Jefferson represented Albemarle County in the Virginia House of Burgesses beginning in 1769. Wythe also served at the same time. Following the passage of theCoercive Acts by the British Parliament in 1774, he wrote a set of resolutions against the acts, which were expanded into A Summary View of the Rights of British America, his first published work. Previous criticism of the Coercive Acts had focused on legal and constitutional issues, but Jefferson offered the radical notion that the colonists had the natural right to govern themselves. Jefferson also argued that Parliament was the legislature of Great Britain only, and had no legislative authority in the colonies. The paper was intended to serve as instructions for the Virginia delegation of the First Continental Congress, but Jefferson's ideas proved to be too radical for that body.
Marriage and family
Wife and children
In 1772, at age 29 Jefferson married the 23-year-old widow Martha Wayles Skelton. They had six children, only two of whom survived to adulthood. Only their oldest daughter Martha lived beyond age 25.
Martha Washington Jefferson (1772–1836), who married Thomas Mann Randolph, Jr., future governor of Virginia. They had twelve children, eleven of whom survived to adulthood.
Jane Jefferson (1774–1775)
stillborn or unnamed son (1777)
Mary Wayles Jefferson (1778–1804), married her cousin John Wayles Eppes, son of Martha's sister, Elizabeth Wayles Eppes. Mary died at age 25 after the birth of her third child; only their son Francis W. Eppes survived to adulthood. Jefferson made his grandson the designated heir of Poplar Forest, originally intended for Mary. In 1829 Francis Eppes moved to Florida, where he had a cotton plantation until the Civil War.
Lucy Elizabeth (1780–1781)
Lucy Elizabeth (1782–1785) (it was the tradition to name subsequent children after one who had died, particularly when the family was also trying to pass down family names). Lucy died while Jefferson was in Paris, prompting him to have his youngest daughter Polly (Mary) sent to him, who was then age nine.
Martha Jefferson died on September 6, 1782, a few months after the birth of her last child. Jefferson never remarried. At his wife's bedside when she died, Jefferson was deeply upset after her death, and often rode on secluded roads to mourn for his wife.
Political career from 1775 to 1800
Rudolph Evans' statue of Jefferson with excerpts from the Declaration of Independence to the right
Drafting a declaration
Jefferson served as a delegate to the Second Continental Congress beginning in June 1775, soon after the outbreak of the American Revolutionary War. When Congress began considering a resolution of independence in June 1776, Jefferson was appointed to a five-man committee to prepare a declaration to accompany the resolution. The committee selected Jefferson to write the first draft probably because of his reputation as a writer. The assignment was considered routine; no one at the time thought that it was a major responsibility. Jefferson completed a draft in consultation with other committee members, drawing on his own proposed draft of the Virginia Constitution, George Mason's draft of the Virginia Declaration of Rights, and other sources.
Jefferson showed his draft to the committee, which made some final revisions, and after Franklin and Adams suggested a few changes, presented it to Congress on June 28, 1776. After voting in favor of the resolution of independence on July 2, Congress turned its attention to the declaration. Over three days of fiery debate, Congress made a few changes in wording and deleted nearly a fourth of the text, most notably a passage critical of the slave trade, changes that Jefferson resented. During the three day debate Jefferson spoke not a word for or against any of the revisions. On July 4, 1776, the wording of theDeclaration of Independence was ratified. Before the signing a prayer was said and in silence the delegates to the convention applied their signature to the document, an act that would be considered treason by the Crown and which would cost them their lives should the revolution fail. The Declaration would eventually become Jefferson's major claim to fame, and his eloquent preamble became an enduring statement of human rights.
In John Trumbull's painting Declaration of Independence, the five-man drafting committee is presenting its work to the Continental Congress. Jefferson is the tall figure in the center laying the Declaration on the desk.
In September 1776, Jefferson returned to Virginia and was elected to the newVirginia House of Delegates. During his term in the House, Jefferson set out to reform and update Virginia's system of laws to reflect its new status as a democratic state. He drafted 126 bills in three years, including laws to abolish primogeniture, establish freedom of religion, and streamline the judicial system. In 1778, Jefferson's "Bill for the More General Diffusion of Knowledge" and subsequent efforts to reduce clerical control led to some small changes at William and Mary College. While in the state legislature Jefferson proposed a bill to eliminate capital punishment for all crimes except murder and treason. His effort to end the death penalty law was defeated.
Governor of Virginia
In 1779, at the age of thirty-six, Jefferson was elected Governor of Virginia and served from 1779–1781. At this time the now united colonies were in the middle of the American Revolutionary War with Britain. Georgia had fallen helpless into the hands of the British, South Carolina was invaded, and Charleston threatened. In his capacity as Governor Jefferson made efforts to prepare Richmond for attack by moving all arms, military supplies and records from Richmond to a foundry located five miles outside of town. Arnold learned of this transfer and was rapidly approaching the foundry. Jefferson then attempted to devise a way for their removal to Westham, seven miles to the north, but he was too late. Arnold's men quickly descended upon and burned the foundry and then proceeded on towards Westham. Upon finding the Prussian ally and military adviser, Baron von Steuben, Arnold chose to return to Richmond where he burned much of the city the following morning. Jefferson at later points in his political career would be criticized, especially by his political opponents, for failing to defend Richmond during this time. 
In January of 1781 Benedict Arnold led an armada of British ships and with 1600 British regulars conducted raids along the James River. Later he would join Lord Cornwallis whose troops were now marching across Virginia from the south. In advance Cornwallis dispatched British officer Banastre Tarleton on a secret expedition to Monticello to capture then Governor Jefferson. Quickly making his way at night Tarleton hoped to catch Jefferson by surprise, however in the midst of the activity and havoc of the invasion a heroic action by a young Virginian named Jack Jouett, a captain in the Virginia militia, thwarted the British capture of Virginia's governor. Jouett had spotted the assembly and departure of Tarleton and his men and making his way to Monticello, by way of various back roads of which he was familiar, arrived at Montecello in time to warn Jefferson, members of the Virginia Assembly and citizens at large.  With little warning Jefferson and his family fled and managed to escape, leaving his home to be captured by British troops. A detachment of Cornwallis' troops, in their march north from the Carolinas, seized the estate along with another plantation which Jefferson owned on the James River. British troops destroyed all his crops, burnt his barns and fences, drove off the cattle, seized all usable horses, cut the throats of the colts, and after setting fires left the plantation a smouldering, blackened waste. Twenty-seven slaves were also captured to which Jefferson later replied.. "Had he carried off the slaves to give them freedom, he would have done right." 
As governor in 1780, he transferred the state capital from Williamsburg to Richmond. He continued to advocate educational reforms at the College of William and Mary, including the nation's first student-policed honor code. In 1779, at Jefferson's behest, William and Mary appointed George Wythe to be the first professor of law in an American university. Many people disliked his tenure, and he did not win office again in Virginia. However, in 1783 he was appointed to Congress by the state legislature.
Notes on the State of Virginia
In the Fall of 1780, Gov. Thomas Jefferson was given a list of 22 questions, by Secretary of the French legation to the United States François Marbois, intended to gather pertinent information on the American colonies. Jefferson's responses to Marbois' "Queries" would become known as Notes on the State of Virginia. Jefferson, scientifically trained, was a member of the American Philosophical Society and had extensive knowledge of western lands from Virginia to Illinois. In a course of 5 years, Jefferson enthusiastically devoted his intellectual energy to the book, which discussed contemporary scientific knowledge, and Virginia's history, politics, and ethnography. Jefferson was aided by Thomas Walker, George R. Clark, and U.S. geographer Thomas Hutchins. The book was first published in France in 1785 and in England in 1787.
Member of Congress
Jefferson was a member of Congress at the time American had won its independence and signed the Treaty of Paris in 1783. The Virginia state legislature appointed Jefferson to the Congress of the Confederation on June 6 of that year, his term beginning on November 1. He was a member of the committee formed to set foreign exchange rates, and in that capacity he recommended that the American currency be based on the decimal system. Jefferson also recommended setting up the Committee of the States, to function as the executive arm of Congress when Congress was not in session. He left Congress when he was elected a minister plenipotentiary on May 7, 1784.
See also: Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States
Minister to France
Memorial plaque on the Champs-Élysées, Paris, France, marking where Jefferson lived while he was Minister to France. The plaque was erected after World War I to commemorate the centenary of Jefferson's founding of the University of Virginia.
In May of 1784 Congress appointed Jefferson to act as Minister to France, serving from 1785 to 1789, replacing Benjamin Franklin, who was now well into his senior years. Franklin was much admired in France by both dignitary and common man alike and so it was a delicate matter for Jefferson to step into his position. When the French Foreign minister Count de Vergennescommented to Jefferson, "You replace Monsieur Franklin I hear", Jefferson replied, "I succeed him, no man can replace him. 
While serving in France Jefferson did not attend the Constitutional Convention in Philadelphia, though he followed the proceedings by correspondence, and was supportive of it.
Beginning in early September 1785, Jefferson collaborated by mail with John Adams in London to outline an anti-piracy treaty with Morocco.  Their work culminated in a treaty that was ratified by Congress on July 18, 1787 and is still in force today, making it the longest unbroken treaty relationship in U.S. history.
He enjoyed the architecture, arts, and the salon culture of Paris. He often dined with many of the city's most prominent people, but sided with the revolutionaries in 1789 French Revolution.While in Paris, Jefferson corresponded with a number of individuals who had important roles in events leading up to the French Revolution. These included marquis de Lafayette and comte de Mirabeau, a popular pamphleteer who repeated ideals that had been the basis for the American Revolution.
Jefferson brought some of his slaves to serve the household, including James Hemings for training as a French chef. After his youngest daughter died, he requested that a young woman slave accompany his daughter Polly to France. Sally Hemings was chosen to travel with Polly, and lived with the Jefferson household for about two years in Paris. It is generally held by modern day scholars that Jefferson began a long-term relationship with Sally Hemings while in Paris; that is what their son Madison Hemings reported in his 1873 memoir, however there are no known accounts from Sally Hemings herself.
Secretary of State
In September of 1789 Jefferson returned to America from France with his daughter. Immediately upon his return President Washington wrote to him urging him to accept a seat in his Cabinet as Secretary of State. After a brief conference Jefferson accepted the appointment.
As George Washington's Secretary of State, (1790–1793) Jefferson and Alexander Hamilton argued over national fiscal policy, especially the funding of the debts of the war. Jefferson later compared Hamilton and the Federalists with "Royalism", and stated the "Hamiltonians were panting after...crowns, coronets and mitres." Jefferson and James Madison founded and led the Democratic-Republican Party. He worked with Madison and his campaign manager John J. Beckley to build a nationwide network of Republican allies.
The French minister said in 1793: "Senator Morris and Secretary of the Treasury Hamilton...had the greatest influence over the President's mind, and that it was only with difficulty that he [Jefferson] counterbalanced their efforts."  Jefferson supported France against Britain when they fought in 1793. Jefferson believed that political success at home depended on the success of the French army in Europe. The French minister in 1793, Edmond-Charles Genêt, caused a crisis when he tried to influence public opinion in appealing to the people, something Jefferson tried to stop.
Break from office
Jefferson retired to Monticello in late 1793 where he continued to oppose the policies of Hamilton and Washington. However, the Jay Treaty of 1794, led by Hamilton, brought peace and trade with Britain – while Madison, with strong support from Jefferson, wanted, "to strangle the former mother country" without going to war. "It became an article of faith among Republicans that 'commercial weapons' would suffice to bring Great Britain to any terms the United States chose to dictate."
Even during the violence of the Reign of Terror, Jefferson refused to disavow the revolution because "To back away from France would be to undermine the cause of republicanism in America."
Election of 1796 and Vice Presidency
As the Democratic-Republican candidate in 1796 he lost to John Adams, but had enough electoral votes to become Vice President (1797–1801). He wrote a manual of parliamentary procedure, but otherwise avoided the Senate.
With the Quasi-War underway, the Federalists under John Adams started rebuilding the military, levied new taxes, and enacted the Alien and Sedition Acts. Jefferson interpreted the Alien and Sedition Acts as an effort to suppress Democratic-Republicans rather than dangerous enemy aliens, and were used to attack his party. Jefferson and Madison rallied support by anonymously writing the Kentucky and Virginia Resolutions, which declared that the federal government had no right to exercise powers not specifically delegated to it by the states.
Election of 1800
Main article: United States presidential election, 1800
Working closely with Aaron Burr of New York, Jefferson rallied his party, attacking the new taxes especially, and ran for the Presidency in 1800. Before the passage of the Twelfth Amendment, a problem with the new union's electoral system arose. He tied with Burr for first place in the electoral college, leaving the House of Representatives (where the Federalists still had some power) to decide the election.
Hamilton convinced his party that Jefferson would be a lesser political evil than Burr and that such scandal within the electoral process would undermine the new constitution. On February 17, 1801, after thirty-six ballots, the House elected Jefferson President and Burr Vice President. Jefferson later removed Burr from the ticket in 1804 after Burr killed Hamilton in a duel.
Jefferson owed his election victory to the South's inflated number of Electors, which counted slaves under the three-fifths compromise.After his election in 1800, some called him the "Negro President", with critics like the Mercury and New-England Palladium of Boston that Jefferson had the gall to celebrate his election as a victory for democracy when he won "the temple of Liberty on the shoulders of slaves."
Main article: Presidency of Thomas Jefferson
Thomas Jefferson took the oath of Office on March 4, 1801, at a time when partisan strife between the Republican and Federalist parties was growing to alarming proportions. Regarded as the 'People's President' news of Jefferson's election was well received in most parts of the new country and was marked by celebrations throughout the Union. He was sworn in by Chief Justice John Marshall at the new Capitol in Washington DC. In contrast to the preceding president John Adams, Jefferson exhibited a dislike of formal etiquette. Unlike Washington, who arrived at his inauguration in a stagecoach drawn by six cream colored horses, Jefferson arrived alone on horseback without guard or escort. He was dressed plainly and after dismounting, retired his own horse himself.
The three major achievements of Jefferson's presidency were the Louisiana Purchase, the winning of the first U.S. war overseas (Barbary War), and the abolition of the slave trade.
Administration, Cabinet and Supreme Court appointments
The Jefferson Cabinet
Secretary of State
Secretary of Treasury
Secretary of War
Levi Lincoln, Sr.
Caesar A. Rodney
Secretary of the Navy
William Johnson – 1804
Henry Brockholst Livingston – 1807
Thomas Todd – 1807
States admitted to the Union:
Ohio – March 1, 1803
Painting of Jefferson by Rembrandt Peale(1805)
First Barbary War
Main article: Barbary Wars
When Jefferson became president in 1801, the United States was at the time paying $80,000 to the Barbary states as a 'tribute' for protection against North African piracy. For decades, the pirates had been capturing American ships and crew members and demanding huge ransoms for their release. Before Independence, from 1775 until 1783, American merchant ships were protected from the Barbary pirates by the naval and diplomatic influence of Great Britain. When the American Revolution began, American ships were protected by the 1778 alliance with France, which required the French nation to protect "American vessels and effects against all violence, insults, attacks ...". On December 20, 1777, Morocco's Sultan Mohammed III declared that the American merchant ships would be under the protection of the sultanate and could thus enjoy safe passage into the Mediterranean and along the coast. The Moroccan-American Treaty of Friendship stands as the U.S.'s oldest non-broken friendship treaty.The one with Morocco has been the longest-lasting treaty with a foreign power.
After the United States gained independence, it had to protect its own merchant vessels. It also had to pay $80,000 as tribute to the Barbary states, as did Britain and France at this time. When Tripoli made new demands on the new President for a prompt payment of $225,000 and an annual payment of $25,000, Jefferson refused. He decided it would be easier to fight the pirates than to continue to pay bribes. The pashaof Tripoli declared war on the United States and the First Barbary War began. As secretary of state and vice president, Jefferson had opposed funds for a Navy to be used for anything more than a coastal defense, however given American shipping interests in the Atlantic and Mediterranean, President Jefferson ordered a fleet of naval vessels to various points in the Mediterranean. He forced Tunis and Algiers into breaking their alliance with Tripoli and forcing it out of the fight. Jefferson also ordered five separate naval bombardments of Tripoli, which restored peace in the Mediterranean for a while.See also: Second Barbary War
In 1803 the United States under Jefferson bought the Louisiana Territory from France, doubling the size of the United States.  At the time France under Napoleon, whom Jefferson despised and feared, was facing imminent war against Britain and with bankruptcy. Jefferson sentJames Monroe and Robert R. Livingston to Paris in 1802 to purchase the city of New Orleans and adjacent coastal areas. At the request of Jefferson, a French noblemen named Pierre Samuel du Pont de Nemours, having close ties with both Jefferson and Napoleon, also helped negotiate the purchase with France. Napoleon was committed to affairs in France and was preparing for war with Britain on the home front and realized he could no longer defend the French territory in America. He astonished everyone by offering to sell the entire territory; the final price was a mere $15 million, which Treasure Secretary Albert Gallatin financed easily. Jefferson had acted contrary to his usual requirement of explicit Constitutional authority and the Federalists criticized him for acting without that authority, but this unique and rare opportunity could not be missed. 
Politically, the Louisiana Purchase would prove to be the most consequential executive decision in American history. Without realizing it at the time Jefferson had purchased the largest fertile tract of land on the planet, allowing the nation to be self sufficient. The purchase also changed the new nation's entire national security strategy by removing both British and French imperial ambitions in America. Opinions vary among historians as to who was the principle player in the purchase, some believing it was Napoleon, while others regard Jefferson's handling of the affair as brilliant as his Declaration of Independence. Others agree with Alexander Hamilton, Jefferson's arch rival, and contribute it to, "dumb luck". Still others concur that it was all of these things. 
Lewis and Clark Expedition
Jefferson had an avid interest in the sciences and had long entertained ideas of exploring the American frontier even before Louisiana was purchased from France. As such Jefferson was a member of the American Philosophical Society, founded in Philadelphia in 1743 byBenjamin Franklin, and served as its President from 1797 to 1815. By the turn of the 18th and 19th centuries the society was well established, staffed and equipped and whose resources were availed by Jefferson who in 1803 sent Meriwether Lewis to Philadelphia for instruction and counseling in botany, mathematics, surveying, astronomy, chemistry and map making, among other subjects.  On January 18, 1803, Jefferson sent a confidential letter to Congress asking for $2,500 to fund the expedition and on February 28, 1803, Congress appropriated the necessary funds for the Expedition.  In 1804 Jefferson sent the Lewis and Clark Expedition (1804–1806), which explored the new territory and opened the American West to settlement and produced a wealth of scientific and geographical knowledge.
Before this advent knowledge of the western part of the continent was scant and incomplete, limited to what had been learned from traders, trappers and various explorers. Jefferson had also hoped to find a water route to the Pacific and establish trade relations with the Indians of the West. The expedition was the first American expedition to the Pacific Coast. Led by Meriwether Lewis and William Clark, the expedition, consisting of about 45 men, had several goals, finding a "direct & practicable water communication across this continent, for the purposes of commerce" (the Northwest Passage). Jefferson directed the men to follow the rivers, map them, and collect scientific data. Jefferson also wanted to establish a U.S. claim of "Discovery" to the Pacific Northwest and Oregon territory by mapping and then documenting an American presence there before Europeans could get a chance to claim the land. The expedition reached the Pacific Ocean by November 1805 and on its return in 1806 it had fulfilled Jefferson's hopes by amassing a considerable body of new data concerning the topographical features of the county and its natural resources, providing details on the flora and fauna as well as the Indian tribes. He also commissioned the Pike Expedition to explore the central region of the Purchase, and the Red River Expedition (1806), which was much less successful.  
Ideas for a national institution for military education were founded during the American Revolution, but it wasn't until 1802 when Jefferson, following the advise of George Washington, John Adams and others,  finally convinced Congress to authorize the funding and building of a military academy at West Point on the Hudson River in New York. On March 16, 1802, Jefferson signed the Military Peace Establishment Act, directing that a corps of engineers be established and "stationed at West Point in the state of New York, and shall constitute a Military Academy."  The Act would provide well-trained officers for a professional army. The officers would be reliable republicans rather than a closed elite as in Europe, for the cadets were to be appointed by Congressmen, and thus exactly reflect the nation's politics. In May 1801 Secretary of War Henry Dearborn announced that the president had "decided in favor of the immediate establishment of a military school at West Point and also on the appointment of Major Jonathan Williams", grandnephew of Benjamin Franklin, to direct "the necessary arrangements, at that place for the commencement of the school." On July 4, 1802, the U.S. Military Academy at West Point formally commenced its role as an institution for scientific and military learning. 
He obtained the repeal of many federal taxes in his bid to rely more on customs revenue. He pardoned people imprisoned under the Alien and Sedition Acts, passed in John Adams' term. He repealed the Judiciary Act of 1801 and removed nearly all of Adams' "midnight judges" from office, which led to the Supreme Court deciding the important case of Marbury v. Madison. He also signed into law a bill that officially segregated the U.S. postal system by not allowing blacks to carry mail.