My understanding is that there is a fundamental contradiction in how Nepali communism is viewed outside Nepal. On the one hand, Nepali communism is thought of as a Chinese export, but on the other, it is widely viewed as a version of Indian communism, which is primarily rooted in caste and ethnic politics. This misconception, I think, stems from viewing Nepali social order as a mini version of the Indo-Gangetic society.
Nepali civil war—to borrow the term from
@Peter_Turchin—was likely a 'counter-elite' movement led by high-caste and relatively privileged people mobilising in the name of the oppressed and the disenfranchised. In that sense, the Nepali Maoist movement was much closer to West Bengal's Naxalite movement that emerged from labour movements and peasant uprisings.
Of course, West Bengal is part of India, but it's much less based on caste politics than the rest of the country.