Question: What treaty was signed by the United Kingdom and President James Polk?

Context paragraphs:
Franklin H. Elmore: Franklin Harper Elmore (October 15, 1799May 29, 1850) was a United States Representative and Senator.  Born in Laurens District, the son of John Archer Elmore, he graduated from the South Carolina College at Columbia in 1819, studied law, was admitted to the bar in 1821 and commenced practice in Walterboro.  He was solicitor for the southern circuit from 1822 to 1836, a colonel on the staff of the Governor from 1824 to 1826, and was elected as a State Rights Democrat to the Twenty-fourth Congress to fill the vacancy caused by the resignation of James H. Hammond.  Elmore was reelected to the Twenty-fifth Congress and served from December 10, 1836, to March 4, 1839.  From 1839 to 1850 he was president of the Bank of the State of South Carolina 1839-1850; he declined appointment by President James Polk as Minister to Great Britain.  Elmore was appointed as a Democrat to the U.S. Senate to fill the vacancy caused by the death of John C. Calhoun and served from April 11, 1850, until his own death in Washington, D.C. in 1850.  He was interred in the First Presbyterian Churchyard in Columbia.

United States elections, 1846: The 1846 United States elections occurred in the middle of Democratic President James Polk's term, during the Second Party System.  The election took place during the Mexican-American War.  Members of the 30th United States Congress were chosen in this election.  Wisconsin joined the union during the 30th Congress.  Democrats kept control of the Senate, but lost control of the House.

Oregon Bill of 1848: The Oregon Bill of 1848, officially titled when approved, "An Act to Establish the Territorial Government of Oregon," was an act of Congress to turn Oregon into an official U.S. Territory.  The bill was passed on August 14, 1848.  It was enacted by the 30th United States Congress, and signed by President James K. Polk.  The bill came into question several years after the Oregon Treaty.  For two years following that treaty, the United States paid little attention to it until news of the Whitman massacre reached Congress.  This provided the impetus to formally establish the Territorial Government of Oregon.  The Act created a territory that encompassed present-day Idaho, Oregon, and Washington; as well as parts of Montana and Wyoming.

President James K. Polk Historic Site: The President James K. Polk Historic Site is a museum and historic location in Mecklenburg County, North Carolina, and a historic site managed by the North Carolina Department of Natural and Cultural Resources' Historic Sites division.  The property was the location of property owned by the parents of President James K. Polk, and exhibits at the historic site serve to tell the story of the President's political career, as well as provide a look into life in North Carolina in the early 19th Century.

Sarah Childress Polk: Sarah Childress Polk (September 4, 1803 – August 14, 1891) was the wife of the 11th President of the United States, James Polk, serving as First Lady of the United States from 1845 to 1849.

Harmoneons: The Harmoneons were a blackface musical singing group in the 19th-century United States.  The group began as the "Albino Family" in 1843, and later became the "Harmoneon Family."  Principal group members included L.V.H. Crosby; Marshall S. Pike (1818-1901); James Power; and John Power Through the years others associated with the group included: F.B. Howe; Francis Lynch; W.H. Mower, manager; T.B. Prendergast; and F.A. Reynolds.  In 1847 the Harmoneons performed for President James Polk at the White House.  The group sang throughout the U.S., including Baltimore, Maryland (1846-1847, 1850, 1853); Trenton, New Jersey (1847); Portsmouth, New Hampshire (1848); Lowell, Mass. (1849); Salem, Mass. (1849); Belfast, Maine (1850, 1852); and in Boston at the Melodeon (1849), Horticultural Hall (1849, 1851), and other venues.  They also toured in Halifax, Nova Scotia.

Ezekiel Polk: Ezekiel Polk (December 7, 1747 – August 31, 1824), American soldier, pioneer and grandfather of President James Knox Polk, was the next youngest of five boys and three girls born to William Polk and Margaret Taylor Polk of Cumberland County, Pennsylvania, near present-day Carlisle.  About 1753 the family moved southwestward to the southern boundary of North Carolina in what would become Mecklenburg County.  His parents appear to have died shortly afterward, and Ezekiel probably was brought up by his older brother Thomas, the senior member of the family, a leader of the local militia and a member of the first and subsequent North Carolina provincial assemblies.  At age 20 Ezekiel, recently married, was named clerk of court in the new county of Tryon across the Catawba River, where he and his bride established themselves on a 100 acre farm just south of Kings Mountain.  In 1772, however, the provincial boundary was surveyed, and Polk's property was discovered to lie in South Carolina.

Oregon Treaty: The Oregon Treaty is a treaty between the United Kingdom and the United States that was signed on June 15, 1846, in Washington, D.C. Signed under the presidency of James K. Polk, the treaty brought an end to the Oregon boundary dispute by settling competing American and British claims to the Oregon Country; the area had been jointly occupied by both Britain and the U.S. since the Treaty of 1818.

Polk County, Arkansas: Polk County is a county located in the U.S. state of Arkansas.  As of the 2010 census, the population was 20,662.  The county seat is Mena.  Polk County is Arkansas's 48th county, formed on November 30, 1844, and named for James Polk, President of the United States.  It is an alcohol prohibition or dry county.

Polk Place: Polk Place was the home of 11th President of the United States James K. Polk and his wife Sarah Childress Polk on Vine Street in Nashville, Tennessee, which he purchased from his mentor Felix Grundy.  It was called "Grundy Place" and was changed to "Polk Place."  It was his final residence and where he died in 1849 at age 53.  After his death his wife continued to reside there.  During the Civil War, Polk Place was considered neutral ground by both the Confederate and Union armies.  In spite of the fact that she had nephews fighting on the Confederate side, Union Generals Ulysses S. Grant and Don Carlos Buell frequently paid their respects to the former first lady.  After a short illness, Mrs. Polk died at Polk Place in 1891, just short of her 88th birthday.  James K. Polk's tomb was located on the front lawn until 1893, when it was moved to the Tennessee State Capitol.  What followed was a long legal dispute centered on James K. Polk's will, after which the heirs of President and Mrs. Polk sold Polk Place.  The state of Tennessee nearly acquired Polk Place and made it the governor's mansion (at the time, the governor of Tennessee stayed in a hotel room).  A developer bought the house and had it demolished in 1900 to build a small apartment building.  The YWCA bought the property in 1909 and built a new state-of-the-art facility.  They sold the building in 1978 and moved to Woodmont Avenue.  The Capitol Hotel (formerly Best Western) now occupies the former site of Polk Place.

Supporting paragraphs: Oregon Bill of 1848 Oregon Treaty
Answer: Oregon Treaty