Republic of the Rio Grande Museum, Historic house museum in downtown San Agustin Historic District, Laredo, United States.

The Republic of the Rio Grande Museum occupies a Mexican adobe house built in 1830 in downtown Laredo. Three restored rooms inside show how the house was furnished and used during that period.

The building served as the seat of government for the Republic of Rio Grande, a short-lived independent state that existed between Texas and Mexico in 1840. The republic lasted only a few months before it dissolved.

The rooms display furniture, photographs, and household items that show how people in the Texas-Mexico borderlands lived and spent their time in the 1800s. Visitors can see the way families arranged their homes and the objects they used every day.

The museum stands in the San Agustin de Laredo Historic District, next to La Posada Hotel and San Agustin Cathedral. Guided tours are offered year-round for school groups and adults. The building is operated by the Webb County Heritage Foundation.

Because of this building's role as the Republic of the Rio Grande capitol, Laredo flew seven flags rather than the six usually counted over Texas. The house later belonged to rancher Bartolomé García, a mayor of Laredo and descendant of town founder Tomas Sanchez.