When we hear the word caste, we think of India, of poverty, inequality, and discrimination. But caste is a European non translatable, from Spanish-Portuguese "Casta". Racial purity or limpieza de sangre was at the root of this system.
When Europeans colonised the Americas 500 years ago, they established a casta system in Mexico. France had three castes - nobility, clergy, and peasants. This unjust system came to and end with the French revolution. The Dutch established a caste system in Sri Lanka. After colonising Philipines, Spain started a caste system there. The unehrliche Leute were the outcastes of Germany, the latrine cleaners, skinners and grave diggers.
England had four castes - king, nobles, knights and peasants. Gongfermours, the toilet cleaners were outcastes in London. The Romanis were outcastes for thousand years.
Caste is quintessentially European.