I suggest all of friends to use the term INDOARYAN TRIBE instead of Bahun Chettri,Thakuri or DAlit. Actually what you should know is that Caste and Race is Different thing. Bahun, chettri, Dalit Thakuri, sarkee fall into same race. Bahun is not a racial term. Can you recognize who is bahun or dalit or chettri just by looking.?They have the same language and cultures.About 500 years ago some indoaryan Entered nepal and made their own socilization here. In a long course of time they developed their own culture,mostlybased on Hindu system but slightly difference than from India.Rani Mukherjee is also a bahun-Bengali, Madhuri is also a bahun...so on but they use differnt language. Newars are also Indoaryan tribe especially higher caste Newar like Shrestha and pradhan.They also came from India and imposed caste system in Kathmandu, That is why newars have also caste system like hajam, dhobi, kami Jyapoo etc. Pradhan means Pradhan Kaji in Malla period. Pradhan were Thakuri--A rajasthani tribe rajpoot. But they socialized in Newari culture and became Newars. But Newars have mixed culture. The local residents of Kathmandu might have been Jyapoo.