Mexican–American War: The United States declares war on the Federal Republic of Mexico following a dispute over the American annexation of the Republic of Texas and a Mexican military incursion.

Mexican–American War

Armed conflict between the US and Mexico (1846–1848)

The Mexican–American War, also known in the United States as the Mexican War, was an invasion of Mexico by the United States Army. It followed the 1845 American annexation of Texas, which Mexico still considered its territory because it refused to recognize the Treaties of…

United States

Country primarily in North America

The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and…

United States declaration of war on Mexico

On May 13, 1846, the United States Congress passed An Act providing for the Prosecution of the existing War between the United States and the Republic of Mexico, thereby declaring war against Mexico. The declaration resulted in the Mexican–American War (1846–48). The act laid…

Second Federal Republic of Mexico

Period of Mexican history from 1846 to 1863

The Second Federal Republic of Mexico refers to the period of Mexican history involving a second attempt to establish a federal government in Mexico after the fall of the unitary Centralist Republic of Mexico in 1846 at the start of the Mexican-American War. It would last up…

Texas annexation

1845 admission of Texas to the US

The Republic of Texas was annexed into the United States and admitted to the Union as the 28th state on December 29, 1845.

Republic of Texas

Historical republic, 1836–1846

The Republic of Texas, or simply Texas, was a country in North America that existed for close to 10 years, from March 2, 1836, to February 19, 1846. Texas shared borders with Centralist Republic of Mexico, the Republic of the Rio Grande, and the United States. The Republic…

Thornton Affair

Part of the Mexican–American War in 1846

The Thornton Affair was a battle in 1846 between the military forces of the United States and Mexico 20 miles (32 km) west upriver from Zachary Taylor's camp along the Rio Grande. The much larger Mexican force defeated the Americans in the opening of hostilities, and was the…

May 13

Day of the year

May 13 is the 133rd day of the year in the Gregorian calendar; 232 days remain until the end of the year.