James K . Polk James Knox Polk ( November 2 , 1795 – June 15 , 1849 ) was the 11th President of the United States ( 1845 – 1849 ) . Polk was born in Mecklenburg County , North Carolina . He later lived in and represented Tennessee . A Democrat , Polk served as the 17th Speaker of the House of Representatives ( 1835 – 1839 ) and Governor of Tennessee ( 1839 – 1841 ) . Polk was the surprise ( dark horse ) candidate for president in 1844 , defeating Henry Clay of the rival Whig Party by promising to annex Texas . Polk was a leader of Jacksonian Democracy during the Second Party System . Polk was the last strong pre – Civil War president , and he is the earliest of whom there are surviving photographs taken during a term in office . He is noted for his foreign policy successes . He threatened war with Britain over the issue of which nation owned the Oregon Country , then backed away and split the ownership of the region with Britain . When Mexico rejected American annexation of Texas , Polk led the nation to a sweeping victory in the Mexican - American War , which gave the United States most of its present Southwest . He secured passage of the Walker tariff of 1846 , which had low rates that pleased his native South , and he established a treasury system that lasted until 1913 . Polk oversaw the opening of the U . S . Naval Academy and the Smithsonian Institution , the groundbreaking for the Washington Monument , and the issuance of the first postage stamps in the United States . He promised to serve only one term and did not run for reelection . He died of cholera three months after his term ended . Scholars have ranked him favorably on the list of greatest presidents for his ability to set an agenda and achieve all of it . Polk has been called the " least known consequential president " of the United States . Early life . James Knox Polk , the first of ten children , was born on November 2 , 1795 in a farmhouse ( possibly a log cabin ) in what is now Pineville , North Carolina in Mecklenburg County , just outside Charlotte . His father , Samuel Polk , was a slaveholder , successful farmer and surveyor of Scots - Irish descent . His mother , Jane Polk ( née Knox ) , was a descendant of a brother of the Scottish religious reformer John Knox . She named her firstborn after her father James Knox . Like most early Scots - Irish settlers in the North Carolina mountains , the Knox and Polk families were Presbyterian . While Jane remained a devout Presbyterian her entire life , Samuel ( whose father , Ezekiel Polk , was a deist ) rejected dogmatic Presbyterianism . When the parents took James to church to be baptized , the father Samuel refused to declare his belief in Christianity , and the minister refused to baptize the child . In 1803 , most of Polk ' s relatives moved to the Duck River area in what is now Maury County , Middle Tennessee ; Polk ' s family waited until 1806 to follow . The family grew prosperous , with Samuel Polk turning to land speculation and becoming a county judge . Polk was home schooled . His health was problematic and in 1812 his pain became so unbearable that he was taken to Dr . Ephraim McDowell of Danville , Kentucky , who operated to remove urinary stones . Polk was awake during the operation with nothing but brandy available for anesthetic , but it was successful . The surgery may have left Polk sterile , as he did not sire any children . When Polk recovered , his father offered to bring him into the mercantile business , but Polk refused . In July 1813 , Polk enrolled at the Zion Church near his home . A year later he attended an academy in Murfreesboro , where he may have met his future wife , Sarah Childress . At Murfreesboro , Polk proved a promising student . In January 1816 , he transferred and was admitted into the University of North Carolina as a second - semester sophomore . The Polks had connections with the university , then a small school of about 80 students : Sam Polk was their land agent for Tennessee , and his cousin , William Polk , was a trustee . While there , Polk joined the Dialectic Society where he regularly took part in debates and learned the art of oratory . His roommate William Dunn Moseley later became the first governor of Florida . Polk graduated with honors in May 1818 . The University later named the lower quad on its main campus , Polk Place . After graduation , Polk traveled to Nashville to study law under renowned Nashville trial attorney Felix Grundy . Grundy became Polk ' s first mentor . On September 20 , 1819 , Polk , with Grundy ' s endorsement , was elected clerk for the Tennessee State Senate . Polk was reelected as clerk in 1821 without opposition , and would continue to serve until 1822 . Polk was admitted to the bar in June 1820 and his first case was to defend his father against a public fighting charge , and secure his release for a one dollar fine . Polk ' s practice was successful as there were many cases arising from debts after the Panic of 1819 . Early political career . In 1822 Polk joined the Tennessee militia as a captain in the cavalry regiment of the 5th Brigade . He was later appointed a colonel on the staff of Governor William Carroll , and was afterwards often referred to or addressed by his military title . Polk ' s oratory became popular , earning him the nickname " Napoleon of the Stump . " In 1822 Polk resigned his position as clerk to run his successful campaign for the Tennessee state legislature in 1823 , in which he defeated incumbent William Yancey , becoming the new representative of Maury County . In October 1823 Polk voted for Andrew Jackson to become the next United States Senator from Tennessee . Jackson won and from then on Polk was a firm supporter of Jackson . Polk courted Sarah Childress , and they married on January 1 , 1824 in Murfreesboro . Polk was then 28 , and Sarah was 20 years old . They had no children . During Polk ' s political career , Sarah assisted her husband with his speeches , gave him advice on policy matters and played an active role in his campaigns . An old story told that Andrew Jackson had encouraged their romance when they began to court . In 1824 , Jackson ran for President but was defeated . Though Jackson had won the popular vote , neither he nor any of the other candidates ( John Quincy Adams , Henry Clay , and William H . Crawford ) had won a majority of the electoral vote . The House of Representatives then had to select the verdict ; Clay , who had received the least amount of electoral votes and dropped from the ballot , supported Adams . Clay ' s support proved to be the deciding factor in the House and Adams was elected President . Adams then offered Clay a position in the Cabinet as Secretary of State . In 1825 , Polk ran for the United States House of Representatives for the Tennessee ' s 6th congressional district . Polk vigorously campaigned in the district . Polk was so active that Sarah began to worry about his health . During the campaign , Polk ' s opponents said that at the age of 29 Polk was too young for a spot in the House , but he won the election and took his seat in Congress . When Polk arrived in Washington , D . C . he roomed in Benjamin Burch ' s boarding house with some other Tennessee representatives , including Samuel Houston . Polk made his first major speech on March 13 , 1826 , in which he said that the Electoral College should be abolished and that the President should be elected by the popular vote . After Congress went into recess in the summer of 1826 , Polk returned to Tennessee to see Sarah , and when Congress met again in the autumn , Polk returned to Washington with Sarah . In 1827 Polk was reelected to Congress . In 1828 , Jackson ran for President again and during the campaign Polk and Jackson corresponded , with Polk giving Jackson advice on his campaign . With Jackson ' s victory in the election Polk began to support the administration ' s position in Congress . During this time , Polk continued to be reelected in the House . In August 1833 , after being elected to this fifth term , Polk became the chair of the House Ways and Means Committee . Speaker of the House . In June 1834 , Speaker of the House Andrew Stevenson resigned , leaving the spot for speaker open . Polk ran against fellow Tennessean John Bell for Speaker , and , after ten ballots , Bell won . However , in 1835 , Polk ran against Bell for Speaker again and won . Polk worked for Jackson ' s policies as speaker , and Van Buren ' s when he succeeded Jackson in 1837 ; he appointed committees with Democratic chairs and majorities , including the New York radical C . C . Cambreleng as Chair of the Ways and Means Committee , although he maintained the facade of traditional bipartisanship . The two major issues during Polk ' s speakership were slavery and the economy , after the Panic of 1837 . Van Buren and Polk faced pressure to rescind the Specie Circular , an act that had been signed by Jackson to boost the economy . The act required that payment for government lands be in gold and silver . However , with support from Polk and his cabinet , Van Buren chose to stick with the Specie Circular . Polk attempted to make a more orderly house . He never challenged anyone to a duel no matter how much they insulted his honor as was customary then . Polk also issued the gag rule on petitions from abolitionists . Polk remains the only president who served as Speaker of the House . Governor of Tennessee . In 1838 , the political situation in Tennessee — where , in 1835 , Democrats had lost the governorship for the first time in their party ' s history — persuaded Polk to return to help the party at home . Leaving Congress in 1839 , Polk became a candidate in the Tennessee gubernatorial election , defeating the incumbent Whig , Newton Cannon by about 2 , 500 votes , out of about 105 , 000 . Polk ' s three major programs during his governorship ; regulating state banks , implementing state internal improvements , and improving education all did not get approval by the legislature . In the presidential election of 1840 , Van Buren was overwhelmingly defeated by a popular Whig , William Henry Harrison . Polk received one electoral vote from Tennessee for in the election . Polk lost his own reelection to James C . Jones , in 1841 , by 3 , 243 votes . He challenged Jones in 1843 , campaigning across the state and publicly debating against Jones , but was defeated again , this time by a slightly greater margin of 3 , 833 votes . Election of 1844 . Polk initially hoped to be nominated for vice president at the Democratic convention , which began on May 27 , 1844 . The leading contender for the presidential nomination was former President Martin Van Buren , who wanted to stop the expansion of slavery . Other candidates included James Buchanan , General Lewis Cass , Cave Johnson , John C . Calhoun , and Levi Woodbury . The primary point of political contention involved the Republic of Texas , which , after declaring independence from Mexico in 1836 , had asked to join the United States , but was refused by Washington . Van Buren opposed the annexation but in doing so lost the support of many Democrats , including former President Andrew Jackson , who still had much influence . Van Buren won a simple majority on the convention ' s first ballot but did not attain the two - thirds supermajority required for nomination . When it became clear after another six ballots that Van Buren would not win the required majority , Polk emerged as a " dark horse " candidate . After an indecisive eighth ballot , the convention unanimously nominated Polk . Before the convention , Jackson told Polk that he was his favorite for the nomination of the Democratic Party . Even with this support , Polk instructed his managers at the convention to support Van Buren if he could win the nomination . This assured that if a deadlocked convention occurred , initial supporters of Van Buren would pick Polk as a compromise candidate for the Democrats . In the end , this is exactly what happened as a result of Polk ' s support of westward expansion . When advised of his nomination , Polk replied : " It has been well observed that the office of President of the United States should neither be sought nor declined . I have never sought it , nor should I feel at liberty to decline it , if conferred upon me by the voluntary suffrages of my fellow citizens . " Because the Democratic Party was splintered into bitter factions , Polk promised to serve only one term if elected , hoping that his disappointed rival Democrats would unite behind him with the knowledge that another candidate would be chosen in four years . Polk ' s Whig opponent in the 1844 presidential election was Henry Clay of Kentucky . ( Incumbent Whig President John Tyler — a former Democrat — had become estranged from the Whigs and was not nominated for a second term . ) The annexation of Texas , which was at the forefront during the Democratic Convention , again dominated the campaign . Polk was a strong proponent of immediate annexation , while Clay seemed more equivocal and vacillating . Another campaign issue , also related to westward expansion , involved the Oregon Country , then under the joint occupation of the United States and the United Kingdom . The Democrats had championed the cause of expansion , informally linking the controversial Texas annexation issue with a claim to the entire Oregon Country , thus appealing to both Northern and Southern expansionists . ( The slogan " Fifty - four Forty or Fight " , often incorrectly attributed to the 1844 election , did not appear until later ; see Oregon boundary dispute . ) Polk ' s consistent support for westward expansion — what Democrats would later call " Manifest Destiny " — likely played an important role in his victory , as his opponent Clay hedged his position . In the election , Polk and his running mate , George M . Dallas , won in the South and West , while Clay drew support in the Northeast . Polk lost both his birth state , North Carolina , and his state of residence , Tennessee , the most recent successful presidential candidate to do so . However , he won New York , where Clay lost votes to the antislavery Liberty Party candidate James G . Birney . Also contributing to Polk ' s victory was the support of new immigrant voters , who opposed the Whigs ' policies . Polk won the popular vote by a margin of about 39 , 000 out of 2 . 6 million , and took the Electoral College with 170 votes to Clay ' s 105 . Polk won 15 states , while Clay won 11 . Presidency ( 1845 – 1849 ) . When he took office on March 4 , 1845 , Polk , at 49 , became the youngest man at the time to assume the presidency . According to a story told decades later by George Bancroft , Polk set four clearly defined goals for his administration : Pledged to serve only one term , he accomplished all these objectives in just four years . By linking acquisition of new lands in Oregon ( with no slavery ) and Texas ( with slavery ) , he hoped to satisfy both North and South . During his presidency James K . Polk was known as " Young Hickory " , an allusion to his mentor Andrew Jackson , and " Napoleon of the Stump " for his speaking skills . Fiscal policy . In 1846 , Congress approved the Walker Tariff ( named after Robert J . Walker , the Secretary of the Treasury ) , which represented a substantial reduction of the high Whig - backed Tariff of 1842 . The new law abandoned " ad valorem " tariffs and set rates independent of the monetary value of the product . Polk ' s actions were popular in the South and West ; however , they were despised by many protectionists in Pennsylvania . In 1846 , Polk approved a law restoring the Independent Treasury System , under which government funds were held in the Treasury and not in banks or other financial institutions . This established independent treasury deposit offices , separate from private or state banks , to receive all government funds . Rivers and Harbors Veto . Congress passed the Rivers and Harbors Bill in 1846 to provide $ 500 , 000 to improve rivers and harbors , but Polk vetoed the bill . It would have provided for federally funded internal improvements on small harbors . Polk believed that this was unconstitutional because the bill unfairly favored particular areas , including ports which had no foreign trade . Polk believed that these problems were local and not national . Polk feared that passing the Rivers and Harbors Bill would encourage legislators to compete for favors for their home districts – a type of corruption that would spell doom to the virtue of the republic . In this regard he followed his hero Andrew Jackson , who had vetoed the Maysville Road Bill in 1830 on similar grounds . Slavery . During his presidency , many abolitionists harshly criticized him as an instrument of the " Slave Power " , and claimed that spreading slavery was the reason he supported annexing Texas and later war with Mexico . Polk stated in his diary that he believed slavery could not exist in the territories won from Mexico , but refused to endorse the Wilmot Proviso that would forbid it there . Polk argued instead for extending the Missouri Compromise line to the Pacific Ocean , which would prohibit the expansion of slavery above 36° 30 ' west of Missouri , but allow it below that line if approved by eligible voters in the territory . William Dusinberre has argued that Polk ' s diary , which he kept during his presidency , was written for later publication , and does not represent Polk ' s policy . Polk was a slaveholder for his entire life . His father , Samuel Polk , had left Polk more than 8 , 000 acres ( 32 km² ) of land , and divided about 53 slaves to his widow and children after he died . James inherited twenty of his father ' s slaves , either directly or from deceased brothers . In 1831 , he became an absentee cotton planter , sending slaves to clear plantation land that his father had left him near Somerville , Tennessee . Four years later Polk sold his Somerville plantation and , together with his brother - in - law , bought 920 acres ( 3 . 7 km² ) of land , a cotton plantation near Coffeeville , Mississippi . He ran this plantation for the rest of his life , eventually taking it over completely from his brother - in - law . Polk rarely sold slaves , although once he became President and could better afford it , he bought more . Polk ' s will stipulated that their slaves were to be freed after his wife Sarah had died . However , the 1863 Emancipation Proclamation and the 1865 Thirteenth Amendment to the United States Constitution freed all remaining slaves in rebel states long before the death of his wife in 1891 . Foreign policy . Polk strongly supported expansion . Democrats believed that opening up more land for yeoman farmers was critical for the success of republican virtue . ( See Manifest Destiny . ) Like most Southerners , he supported the annexation of Texas . To balance the interests of North and South , he wanted to acquire the Oregon Country ( present - day Oregon , Washington , Idaho , and British Columbia ) as well . He sought to purchase California , which Mexico had neglected . Oregon territory . Polk put heavy pressure on Britain to resolve the Oregon boundary dispute . Since 1818 , the territory had been under the joint occupation and control of the United Kingdom and the United States . Previous U . S . administrations had offered to divide the region along the 49th parallel , which was not acceptable to Britain , as they had commercial interests along the Columbia River . Although the Democratic platform asserted a claim to the entire region , Polk was willing to compromise . When the British again refused to accept the 49th parallel boundary proposal , Polk broke off negotiations and returned to the Democratic platform " All Oregon " demand ( which called for all of Oregon up to the 54 - 40 line that marked the southern boundary of Russian Alaska ) . " 54 - 40 or fight ! " now became a popular rallying cry among Democrats Polk wanted territory , not war , so he compromised with the British Foreign Secretary , Lord Aberdeen . The Oregon Treaty of 1846 divided the Oregon Country along the 49th parallel , the original American proposal . Although there were many who still clamored for the entire territory , the treaty was approved by the Senate . By settling for the 49th parallel , Polk angered many midwestern Democrats . Many of these Democrats believed that Polk had always wanted the boundary at the 49th , and that he had fooled them into believing he wanted it at the 54th parallel . The portion of Oregon territory acquired by the United States later formed the states of Washington , Oregon , and Idaho , and parts of the states of Montana and Wyoming . Texas . Upon hearing of Polk ' s election to office , Tyler urged Congress to pass a joint resolution admitting Texas to the Union ; Congress complied on February 28 , 1845 . Texas promptly accepted the offer and officially became a state on December 29 , 1845 . The annexation angered Mexico , which had lost Texas in 1836 . Mexican politicians had repeatedly warned that annexation would lead to war . Nonetheless , just days after the resolution passed Congress , Polk declared in his inaugural address that only Texas and the United States would decide whether to annex . Mexican - American War . After the Texas annexation , Polk turned his attention to California , hoping to acquire the territory from Mexico before any European nation did so . The main interest was San Francisco Bay as an access point for trade with Asia . In 1845 , he sent diplomat John Slidell to Mexico to purchase California and New Mexico for $ 24 – 30 million . Slidell ' s arrival caused political turmoil in Mexico after word leaked out that he was there to purchase additional territory and not to offer compensation for the loss of Texas . The Mexicans refused to receive Slidell , citing a technical problem with his credentials . In January 1846 , to increase pressure on Mexico to negotiate , Polk sent troops under General Zachary Taylor into the area between the Nueces River and the Rio Grande — territory that was claimed by both the U . S . and Mexico . Slidell returned to Washington in May 1846 , having been rebuffed by the Mexican government . Polk regarded this treatment of his diplomat as an insult and an " ample cause of war " , and he prepared to ask Congress for a declaration of war . Meanwhile Taylor crossed the Rio Grande and briefly occupied Matamoros , Tamaulipas . Taylor continued to blockade ships from entering the port of Matamoros . Mere days before Polk intended to make his request to Congress , he received word that Mexican forces had crossed the Rio Grande area and killed eleven American soldiers . Polk then made this the " casus belli " , and in a message to Congress on May 11 , 1846 , he stated that Mexico had " invaded our territory and shed American blood upon the American soil . " Some Whigs , such as Abraham Lincoln , challenged Polk ' s version of events , but Congress overwhelmingly approved the declaration of war . Many Whigs feared that opposition would cost them politically by casting themselves as unpatriotic for not supporting the war effort . In the House , antislavery Whigs led by John Quincy Adams voted against the war ; among Democrats , Senator John C . Calhoun was the most notable opponent of the declaration . Military action . Polk selected the top generals and set the military strategy of the war . By the summer of 1846 , American forces under General Stephen W . Kearny had captured New Mexico . Meanwhile , Army captain John C . Frémont led settlers in northern California to overthrow the Mexican garrison in Sonoma ( in the Bear Flag Revolt ) . General Zachary Taylor , at the same time , was having success on the Rio Grande , although Polk did not reinforce his troops there . The United States also negotiated a secret arrangement with Antonio López de Santa Anna , the Mexican general and dictator who had been overthrown in 1844 . Santa Anna agreed that , if given safe passage into Mexico , he would attempt to persuade those in power to sell California and New Mexico to the United States . Once he reached Mexico , however , he reneged on his agreement , declared himself President , and tried to drive the American invaders back . Santa Anna ' s efforts , however , were in vain , as Generals Taylor and Winfield Scott destroyed all resistance . Scott captured Mexico City in September 1847 , and Taylor won a series of victories in northern Mexico . Even after these battles , Mexico did not surrender until 1848 , when it agreed to peace terms set out by Polk . Peace : the Treaty of Guadalupe Hidalgo . Polk sent diplomat Nicholas Trist to negotiate with the Mexicans . Lack of progress prompted the President to order Trist to return to the United States , but the diplomat ignored the instructions and stayed in Mexico to continue bargaining . Trist successfully negotiated the Treaty of Guadalupe Hidalgo in 1848 , which Polk agreed to ratify , ignoring calls from Democrats who demanded that all Mexico be annexed . The treaty added 1 . 2 million square miles ( 3 . 1 million square kilometers ) of territory to the United States ; Mexico ' s size was halved , while that of the United States increased by a third . California , Nevada , Utah , most of Arizona , and parts of New Mexico , Colorado and Wyoming were all included in the Mexican Cession . The treaty also recognized the annexation of Texas and acknowledged American control over the disputed territory between the Nueces River and the Rio Grande . Mexico , in turn , received $ 15 million . The war claimed fewer than 20 , 000 American lives but over 50 , 000 Mexican ones . It may have cost the United States $ 100 million . Finally , the Wilmot Proviso injected the issue of slavery in the new territories , even though Polk had insisted to Congress and in his diary that this had never been a war goal . The treaty , however , needed ratification by the Senate . In March 1848 , the Whigs , who had been so opposed to Polk ' s policy , suddenly changed position . Two - thirds of the Whigs voted for Polk ' s treaty . This ended the war and legalized the acquisition of the territories . The war had serious consequences for Polk and the Democrats . It gave the Whig Party a unifying message of denouncing the war as an immoral act of aggression carried out through abuse of power by the president . In the 1848 election , however , the Whigs nominated General Zachary Taylor , a war hero , and celebrated his victories . Taylor refused to criticize Polk . As a result of the strain of managing the war effort directly and in close detail , Polk ' s health markedly declined toward the end of his presidency . Cuba . In mid - 1848 , President Polk authorized his ambassador to Spain , Romulus Mitchell Saunders , to negotiate the purchase of Cuba and offer Spain up to $ 100 million , an astounding sum at the time for one territory , equal to $ in present day terms . Cuba was close to the United States and had slavery , so the idea appealed to Southerners but was unwelcome in the North . However , Spain was still making huge profits in Cuba ( notably in sugar , molasses , rum , and tobacco ) , and thus the Spanish government rejected Saunders ' overtures . Department of the Interior . One of Polk ' s last acts as President was to sign the bill creating the Department of the Interior ( March 3 , 1849 ) . This was the first new cabinet position created since the early days of the Republic . Polk had misgivings about the federal government usurping power over public lands from the states ; however , the delivery of the legislation on his last full day in office gave him no time to find constitutional grounds for a veto , or to draft a sufficient veto message , so Polk signed the bill . Judicial appointments . Supreme Court . Polk appointed the following Justices to the U . S . Supreme Court : Woodbury was from New Hampshire , and Grier from Pennsylvania . Polk also nominated George W . Woodward of Pennsylvania in 1846 , but the United States Senate rejected the nomination . Other judicial appointments . Polk appointed eight other federal judges , one to the United States Circuit Court of the District of Columbia , and seven to various United States district courts . Congress . 29th Congress ( March 4 , 1845 – March 4 , 1847 ) 30th Congress ( March 4 , 1847 – March 4 , 1849 ) Post - presidency . Polk ' s time in the White House took its toll on his health . Full of enthusiasm and vigor when he entered office , Polk left on March 4 , 1849 , exhausted by his years of public service . He lost weight and had deep lines on his face and dark circles under his eyes . He is believed to have contracted cholera in New Orleans , Louisiana , on a goodwill tour of the South after leaving the White House . He died at his new home , Polk Place , in Nashville , Tennessee , at 3 : 15 pm on June 15 , 1849 , three months after leaving office . He was buried on the grounds of Polk Place . Polk ' s last words illustrate his devotion to his wife : " I love you , Sarah . For all eternity , I love you . " She lived at Polk Place for over forty years after his death . She died on August 14 , 1891 . Polk was also survived by his mother , Jane Knox Polk , who died on January 11 , 1852 . Polk had the shortest retirement of all Presidents at 103 days . He was the youngest former president to die in retirement at the age of 53 . Along with George Washington , Andrew Johnson , Chester Arthur , Calvin Coolidge , and Lyndon Johnson he is one of six presidents to have died while his direct successor was in office . He and his wife are buried in a tomb on the grounds of the Tennessee State Capitol in Nashville , Tennessee . The tomb was moved to this location from their downtown Nashville mansion , Polk Place , in 1893 . Reputation . Polk ' s historic reputation was largely formed by the attacks made on him in his own time ; the Whigs claimed that he was drawn from a well - deserved obscurity ; Senator Tom Corwin of Ohio remarked " James K . Polk , of Tennessee ? " After that " , who is safe ? " The Republican historians of the nineteenth century inherited this view . Polk was a compromise between the Democrats of the North , like David Wilmot and Silas Wright , and the plantation owners who were led by John C . Calhoun ; the northern Democrats thought that when they did not get their way , it was because he was the tool of the slaveholders , and the conservatives of the South insisted that he was the tool of the northern Democrats . These views were long reflected in the historical literature , until Arthur M . Schlesinger , Jr and Bernard De Voto argued that Polk was nobody ' s tool , but set his own goals and achieved them . Polk is now recognized , not only as the strongest president between Jackson and Lincoln , but the president who made the United States a coast - to - coast nation . When historians began ranking the presidents in 1948 , Polk ranked 10th in Arthur M . Schlesinger ’ s poll . and has subsequently ranked 8th in Schlesinger ’ s 1962 poll , 11th in the Riders - McIver Poll ( 1996 ) , 11th in the most recent Siena Poll ( 2002 ) , 9th in the most recent " Wall Street Journal " Poll ( 2005 ) , and 12th in the latest C - Span Poll ( 2009 ) . Polk biographers over the years have sized up the magnitude of Polk ’ s achievements and his legacy , particularly his two most recent . “ There are three key reasons why James K . Polk deserves recognition as a significant and influential American president , ” Walter Borneman wrote . “ First , Polk accomplished the objectives of his presidential term as he defined them ; second , he was the most decisive chief executive before the Civil War ; and third , he greatly expanded the executive power of the presidency , particularly its war powers , its role as commander - in - chief , and its oversight of the executive branch . " President Harry S . Truman summarized this view by saying that Polk was " a great president . Said what he intended to do and did it . " While Polk ’ s legacy thus takes many forms , the most outstanding is the map of the continental United States , whose landmass he increased by a third . “ To look at that map , ” Robert Merry concluded , “ and to take in the western and southwestern expanse included in it , is to see the magnitude of Polk ’ s presidential accomplishments . ” Nevertheless , Polk ' s aggressive expansionism has been criticized on ethical grounds . He believed in " Manifest Destiny " even more than most did . Referencing the Mexican - American War , General Ulysses S . Grant stated that " I was bitterly opposed to the [ Texas annexation ] , and to this day regard the war , which resulted , as one of the most unjust ever waged by a stronger against a weaker nation . It was an instance of a republic following the bad example of European monarchies , in not considering justice in their desire to acquire additional territory . " Whig politicians , including Abraham Lincoln and John Quincy Adams , contended that the Texas Annexation and the Mexican Cession enhanced the pro - slavery factions of the United States . Unsatisfactory conditions pertaining to the status of slavery in the territories acquired during the Polk administration led to the Compromise of 1850 , one of the primary factors in the establishment of the Republican Party and later the beginning of the American Civil War . Humorously , Sam Houston is said to have observed that Polk was " a victim of the use of water as a beverage " .