Question: The Mexican Cession of 1848 is a historical name in the United States for the region of the modern day southwestern United States that Mexico ceded to the U.S. in the Treaty of Guadalupe Hidalgo in 1848, it had not been part of the areas east of the Rio Grande which had been claimed by the Republic of Texas, though the Texas annexation resolution in which year,incorporation of the Republic of Texas into the United States of America, which was admitted to the Union as the 28th state, had not specified the southern and western boundary of Texas?

full_context: Document 1: Texas secession movements: Texas secession movements principally focus on the secession of Texas during the American Civil War and the activities of organizations that have existed since the 1990s. The United States Constitution does not address secession of states and the issue was a topic of debate from after the Revolutionary War up until the Civil War, when the Supreme Court ruled, in "Texas v. White," that states cannot secede. Texas claimed to be a sovereign state for nine years prior to the negotiated annexation with the United States, but its claim was not recognized by Mexico, nor did Texas actually control the entirety of its claimed territory. This history has affected the state's politics ever since, including its standing in the Confederacy in the Civil War to education and even tourism in the 20th century. Modern secession efforts have existed in the state at least since the 1990s, focusing first on the Republic of Texas organization founded by Richard Lance McLaren and later on the Texas Nationalist Movement headed by Daniel Miller.
Document 2: Army of the Republic of Texas: The Army of the Republic of Texas was the land-based component of the armed forces for the Republic of Texas. It directly descended from the Texian Army, which was established on October 2, 1835, to fight for independence from Mexico in the Texas Revolution. The army was provisionally formed from the Consultation in November 1835, and officially established on September 5, 1836, from Article II, Section 5 of the Constitution of the Republic of Texas. After Texas' annexation by the United States, the Army of the Republic of Texas was merged into the United States Army. Today, the 141st Infantry Regiment trace their lineage back to the Texas Revolution.
Document 3: List of battles fought in Colorado: This list of battles fought in Colorado is an incomplete list of military and other armed confrontations that have occurred within the boundaries of the modern US State of Colorado since European contact. The region was part of the Viceroyalty of New Spain from 1535 to 1682, New France from 1682 to 1762, Kingdom of Spain from 1762 to 1800, French First Republic 1800 to 1803, and part of the United States of America 1803–present (boundaries were disputed by Spain). The southern portion of Colorado was considered by Spain as part of its northern territories. Large portions of Colorado were subsequently under the administrative control of Mexico from 1800 to 1835, and the Republic of Texas from 1836 to 1846. Full administrative control of Colorado was established on February 2, 1848 with the signing of the Treaty of Guadalupe Hidalgo which ended the Mexican–American War.
Document 4: United States Boundary Commissioner: Article V of the TREATY OF PEACE, FRIENDSHIP, LIMITS, AND SETTLEMENT BETWEEN THE UNITED STATES OF AMERICA AND THE UNITED MEXICAN STATES CONCLUDED AT GUADALUPE HIDALGO (known commonly as the Treaty of Guadalupe Hidalgo ) declared that the new boundary between the two republics of the United States and Mexico would lay "three leagues from land, opposite the mouth of the Rio Grande, otherwise called Rio Bravo del Norte, or Opposite the mouth of its deepest branch, if it should have more than one branch emptying directly into the sea; from thence up the middle of that river, following the deepest channel, where it has more than one, to the point where it strikes the southern boundary of New Mexico; thence, westwardly, along the whole southern boundary of New Mexico (which runs north of the town called Paso) to its western termination; thence, northward, along the western line of New Mexico, until it intersects the first branch of the river Gila; (or if it should not intersect any branch of that river, then to the point on the said line nearest to such branch, and thence in a direct line to the same); thence down the middle of the said branch and of the said river, until it empties into the Rio Colorado; thence across the Rio Colorado, following the division line between Upper and Lower California, to the Pacific Ocean. " It delineated the boundary through its text but wasn't written with much knowledge of the area's actually geography; A commissioner and surveyor from each country were appointed to precisely locate landmarks and accurately map the new border, relying on the treaty as their guide.
Document 5: Florida Territory: The Territory of Florida was an organized incorporated territory of the United States that existed from March 30, 1822, until March 3, 1845, when it was admitted to the Union as the State of Florida. Originally the Spanish territory of "La Florida", and later the provinces of East and West Florida, it was ceded to the United States as part of the 1819 Adams–Onís Treaty. It was governed by the Florida Territorial Council.
Document 6: Botiller v. Dominguez: Botiller v. Dominguez, 130 U.S. 238 (1889), was a decision by the United States Supreme Court dealing with the validity of Spanish or Mexican land grants in the Mexican Cession, the region of the present day southwestern United States that was ceded to the U.S. by Mexico in 1848 under the Treaty of Guadalupe Hidalgo.
Document 7: Texas annexation: The Texas annexation was the 1845 incorporation of the Republic of Texas into the United States of America, which was admitted to the Union as the 28th state on December 29, 1845.
Document 8: Geography of Mexico: The geography of Mexico describes the geographic features of Mexico, a country in the Americas. Mexico is located at about 23° N and 102° W in the southern portion of North America. From its farthest land points, Mexico is a little over 3,200 km in length. Mexico is bounded to the north by the United States (specifically, from west to east, by California, Arizona, New Mexico, and Texas), to the west and south by the Pacific Ocean, to the east by the Gulf of Mexico, and to the southeast by Belize, Guatemala, and the Caribbean Sea. The northernmost constituent of Latin America, it is the most populous Spanish-speaking country in the world. Mexico is the world's 13th largest country, three times the size of Texas.
Document 9: James K. Polk: James Knox Polk (November 2, 1795 – June 15, 1849) was the 11th President of the United States (1845–49). He previously served as the 13th Speaker of the House of Representatives and as Governor of Tennessee. A protege of Andrew Jackson, Polk was a member of the Democratic Party and an adherent of Jacksonian democracy and Manifest Destiny. During his presidency, the United States expanded significantly with the annexation of Republic of Texas, the Oregon Treaty, and the conclusion of the Mexican-American War.
Document 10: Reconquista (Mexico): The Reconquista ("reconquest") is a term that is used (not exclusively) to describe the vision by different individuals, groups, and/or nations that the U.S. Southwest should be politically or culturally conquered by Mexico. These opinions are often formed on the basis that those territories had been claimed by Spain for centuries and had been claimed by Mexico from 1821 until being ceded to the United States in the Texas annexation (1845) and the Mexican Cession (1848), as a consequence of the Mexican American War.
Document 11: Mexican Cession: The Mexican Cession of 1848 is a historical name in the United States for the region of the modern day southwestern United States that Mexico ceded to the U.S. in the Treaty of Guadalupe Hidalgo in 1848. It had not been part of the areas east of the Rio Grande which had been claimed by the Republic of Texas, though the Texas annexation resolution two years earlier had not specified the southern and western boundary of Texas. The Mexican Cession (529,000 sq. miles) was the third largest acquisition of territory in US history. The largest was the Louisiana Purchase, with some 827,000 sq. miles, followed by the acquisition of Alaska (about 586,000 sq. miles).
Document 12: Treaty of Guadalupe Hidalgo: The Treaty of Guadalupe Hidalgo ("Tratado de Guadalupe Hidalgo" in Spanish), officially entitled the Treaty of Peace, Friendship, Limits and Settlement between the United States of America and the Mexican Republic, is the peace treaty signed on February 2, 1848, in the Villa de Guadalupe Hidalgo (now a neighborhood of Mexico City) between the United States and Mexico that ended the Mexican–American War (1846–48). The treaty came into force on July 4, 1848.
Document 13: Texas v. White: Texas v. White, 74 U.S. 700 (1869) was a case argued before the United States Supreme Court in 1869. The case involved a claim by the Reconstruction government of Texas that United States bonds owned by Texas since 1850 had been illegally sold by the Confederate state legislature during the American Civil War. The state filed suit directly with the United States Supreme Court, which, under the United States Constitution, retains original jurisdiction on certain cases in which a state is a party.
Document 14: List of battles fought in New Mexico: This list of battles fought in New Mexico is an incomplete list of military and other armed confrontations that have occurred within the boundaries of the modern U.S. State of New Mexico since European contact. The region was part of the Viceroyalty of New Spain from 1535 to 1682, New France from 1682 to 1762, Kingdom of Spain from 1762 to 1800, French First Republic 1800 to 1803, and Mexico from 1803-1848. Portions of New Mexico were under the administrative control of the Republic of Texas from 1836 to 1846. Full administrative control of New Mexico was established on February 2, 1848 with the signing of the Treaty of Guadalupe Hidalgo which ended the Mexican–American War.
Document 15: University of Texas at Austin: The University of Texas at Austin (UT, UT Austin, or Texas) is a public research university and the flagship institution of the University of Texas System. Founded in 1881 as "The University of Texas," its campus is located in Austin, Texas, approximately 1 mile (1.6 km) from the Texas State Capitol. UT Austin was inducted into the Association of American Universities in 1929, becoming only the third university in the American South to be elected. The institution has the nation's eighth-largest single-campus enrollment, with over 50,000 undergraduate and graduate students and over 24,000 faculty and staff.
ground_truth: 1845