Political prisoners, Jehovah's Witnesses, and homosexuals were sent to concentration camps as punishment. Members of these three groups were not targeted, as were Jews and Roma, for systematic murder. Nevertheless, many died in the camps from starvation, disease, exhaustion, and brutal treatment.
The federal prison on Alcatraz Island in the chilly waters of California's San Francisco Bay housed some of America's most difficult and dangerous felons during its years of operation from 1934 to 1963.