As the United States moved westward, settlement and expansion hinged on protection by the military. Two African American cavalry regiments, known as the Buffalo Soldiers, were placed in the tense and tenuous position between Native Americans and European settlers. They also worked on infrastructure, like the railroads and telegraph lines that made westward expansion possible. For Buffalo Soldiers, military service offered the opportunity for a better life, and a greater level of independence and respect for their rights not yet widely found in American society.