Neeta Ji, Caste system did not exist in early time of Nepal's history. It was widely used in India however. Caste system was introduced by "Brahmins" for the same reason "Catholic Church" to involve in politics in Med-evil period...for their own good and power. Being a "Brahmin" mean embodiment of Brahma (God of Creator). Therefore they are superior to every other living thing. My blood boils as I type. Anyway, this despicable system was introduced in Nepal by the king "Jayasthiti Malla", along with the measurement units like Mana, Pathi, Dhadni, and etc. Higher ranking castes embraced it and lower ranking castes tolerated it. Now, you know why we hate each other so much.