bed the majority of slaves brought from
             Africa in the 18th and 19th centuries into its cotton and sugar plantations
             (Excerpted from a nice discussion to be found at
             http://www.geokey.de/jobusa/hinweise.landeskunde.ethnic_and_racial_minoritie
             s.htm). This century has seen two important migrations of blacks - one to
             the North, which began in 1915, and one to the Western states which began
             in 1940: both were caused by a World War and focused on the search for jobs
             (Excerpted from a nice discussion to be found at
             http://www.geokey.de/jobusa/hinweise.landeskunde.ethnic_and_racial_minoritie
             Hispanics are another major minority group in the US, with nearly 6.5%
             of the total US population being of Spanish origin: this group may be
             55% Mexican-Americans (Chicanos), 15.8% Puerto Ricans, and 6.1% Cubans
             (Excerpted from a nice discussion to be found at
             http://www.geokey.de/jobusa/hinweise.landeskunde.eth
             ...