Historians in the 20th century recognized 250 to 311 slave uprisings in U.S. Slave traders and potential buyers would analyze a slave's back again for whipping scars a large number of injuries would be observed as evidence of laziness or rebelliousness, somewhat than the past master's brutality, and would decreased the slave's cost. The Washington, D.C., metropolitan area is also house to big Eritrean and Somali communities.