Historians broadly agree that lynchings were a method of social and racial control meant to terrorize black Americans into submission, and into an inferior racial caste position. They became widely practiced in the US south from roughly 1877, the end of post-civil war reconstruction, through 1950.
A typical lynching would involve criminal accusations, often dubious, against a black American, an arrest, and the assembly of a “lynch mob” intent on subverting the normal constitutional judicial process.
Victims would be seized and subjected to every imaginable manner of physical torment, with the torture usually ending with being hung from a tree and set on fire. More often than not, victims would be dismembered and mob members would take pieces of their flesh and bone as souvenirs.
In a great many cases, the mobs were aided and abetted by law enforcement (indeed, they often were the same people). Officers would routinely leave a black inmate’s jail cell unguarded after rumors of a lynching began to circulate to allow for a mob to kill them before any trial or legal defense could take place.