Timeline: 1844 - 1848

Text version of the timeline appears below. View interactive version of timeline on Home Page.


June 6 - U.S. Senate defeats treaty of annexation with Texas

November - James K. Polk defeats Henry Clay to become eleventh president of the United States

December 5-7 - Santa Anna deposed; José Joaquín Herrera elected as interim president of Mexico


January 2-10 - Santa Anna attacks Puebla

January 14 - Santa Anna captured by government forces

March 1 - U.S. President John Tyler signs the Brown Resolution, offering Texas terms of annexation

March 4 - James Knox Polk is inaugurated as the eleventh president of the United States

March 31 - In response to passage of the Brown Resolution, Mexico's minister to the U.S., Juan N. Almonte, requests his passports, breaking off diplomatic relations between the two countries

April 5 - Mexican president Herrera sends Antonio López de Santa Anna into exile in Cuba

July - President James K. Polk orders General Zachary Taylor to march to Corpus Christi to defend Texas frontier, and dispatches a naval squadron to the Gulf of Mexico

July 4 - Texas convention votes in favor of annexation to the United States

November - U.S. minister John Slidell arrives in Mexico

December 14 - San Luís Potosí garrison calls for the overthrow of Herrera

December 30 - Government of José Joaquín Herrera collapses in Mexico City


January 1 - The Yucatán declares its independence from Mexico and its neutrality in the war with the United States

January 4 - General Mariano Paredes takes the oath of office as president in Mexico City

January 13 - President Polk orders Zachary Taylor to march from Corpus Christi to the Rio Grande and orders a blockade of Vera Cruz

March - Taylor marches to Rio Grande; John Slidell leaves Mexico

March 18 - In Matamoros, Mexican General Francisco Mejia issues a proclamation threatening hostilities against U.S. troops

April - General Mariano Arista takes command of the Mexican Army of the North

April 25 - Thornton Affair - U.S. dragoons attacked by Mexican cavalry on east bank of Rio Grande

May 3-8 - Fort Texas Siege

May 8 - Battle of Palo Alto; John Slidell meets with President Polk

May 9 - News arrives in Washington of the Thornton Affair

May 11 - President's war message read to Congress

May 13 - United States declares war against Mexico

May 18 - U.S. troops occupy Matamoros

June 14 - Bear Flag revolt declared in California

July 7 - U.S. naval forces occupy Monterey, California

July 14 - U.S. forces occupy Camargo, Tamaulipas

July 28 - General Paredes deposed in Mexico City by Mariano Salas

July 30 - General Taylor issues orders for movement of troops from Fort Brown to Camargo

August - Pedro de Ampudia appointed commander of the Army of the North

August 16 - Santa Anna returns to Mexico from exile in Cuba

August 18 - U.S. forces under General Stephen W. Kearny occupy Santa Fe, New Mexico

August 19 - U.S. troops Camargo begins march to Monterrey, Nuevo Leon

September 21-24 - Battle of Monterrey

October 7 - Battle of Dominguez Rancho, Southern California

November 14 - U.S. Navy seizes Tampico

November 16 - U.S. forces occupy Saltillo; Battle of Natividad, Northern California

November 17 - Polk orders a seaborne invasion of Vera Cruz

December - Valentín Gómez Farías assumes the duties of acting president

December 6 - Battle of San Pasqual, California

December 25 - Battle of El Brazito, New Mexico


January 2 - Battle of Santa Clara, California

January 8 - Battle of Rio San Gabriel (Los Angeles), California

January 9 - Battle of La Mesa (Los Angeles), California

January 11 - Acting President Valentín Goméz Farías issues edict confiscating church property

January 19 - Taos Revolt begins; U.S. territorial governor Charles Bent killed

January 24 - Battles of Cañada and Mora, New Mexico

January 29 - Battle of Emudo Pass, New Mexico

February 3-4 - Battle of Pueblo de Taos, New Mexico

February 22-23 - Battle of Buena Vista (Angostura)

February 26 - Polkos Revolt begins in Mexico City

February 28 - Battle of the Sacramento, Northern Mexico

March 9 - 10,000 U.S. troops land on beaches by Navy at Veracruz

March 21 - Polkos Revolt ends

March 22-27 - Siege and bombardment of Veracruz

March 29 - Mexican forces at Veracruz surrender

April 18 - Battle of Cerro Gordo; Battle of Tuxpan

May 15 - Scott occupies Puebla

May 20 - Santa Anna assumes the presidency

August 19 - Battle of Contreras (Padierna)

August 20 - Battle of Churubusco; San Patricio battalion captured

September 8 - Battle of Molino Del Rey

September 13 - Battle of Chapultepec

September 13-14 - Battle for Mexico City

September 14 - Siege of Puebla begins

September 15 - Santa Anna resigns as president of Mexico; U.S. forces under General Winfield Scott occupy Mexico City

October 9 - Battle of Huamantla

October 12 - Siege of Puebla ends

December 22 - Abraham Lincoln presents his "spot resolutions" in Congress, challenging Polks' reasons for declaring war against Mexico


January 24 - Gold discovered at Sutter's Mill, northern California

February 2 - Treaty of Guadalupe Hidalgo signed

February 4 - Last battle of the war fought at Santa Cruz de Rosales, New Mexico

March - Santa Anna departs for exile in Jamaica

March 10 - U.S. Senate ratifies Treaty of Guadalupe Hidalgo, with amendments

May 25 - Mexican Congress ratifies Treaty of Guadalupe Hidalgo

June 3 - José Joaquín Herrera elected to two-year presidential term

July 4 - President Polk formally announces ratification of Treaty of Guadalupe Hidalgo

August 2 - Last U.S. troops leave Mexico

November - General Zachary Taylor elected 12th U.S. president