Members of the U.S. Army's all-black 25th Infantry Regiment were accused of killing a white bartender and wounding a white police officer in Brownsville, Texas, despite exculpatory evidence.

The 25th Infantry Regiment was an infantry regiment of the United States Army activated in 1866 and deactivated in 1957. One of the "Buffalo Soldier" units, the racially segregated regiment saw action during the American Indian Wars, Spanish–American War, Philippine–American War and World War II.

The Brownsville affair, or the Brownsville raid, was an incident of racial discrimination that occurred in 1906 in the Southwestern United States due to resentment by white residents of Brownsville, Texas, of the Buffalo Soldiers, black soldiers in a segregated unit stationed at nearby Fort Brown. When a white bartender was killed and a white police officer wounded by gunshots one night, townspeople accused the members of the African-American 25th Infantry Regiment. Although their commanders said the soldiers had been in the barracks all night, evidence was allegedly planted against the men.

Brownsville is a city in the U.S. state of Texas and the county seat of Cameron County, located on the western Gulf Coast in South Texas, adjacent to the border with Matamoros, Tamaulipas, Mexico. The city covers 145.2 sq mi (376.066 km²), and had a population of 186,738 at the 2020 census. As of the 2020 U.S. Census, it is the 136th-most populous city in the United States and 18th-most populous in Texas. It is part of the Matamoros–Brownsville metropolitan area. The city is known for its year-round subtropical climate, deep-water seaport, and Hispanic culture.