Is Raavana a rakshasa or a brahmin and how he can be a king too?
Basically, the 4 varnas (Brahmana, Kshatriya, Vaishya, Shudra) exist in every jati (deva, manushya, gandharva, rakshasa, pishacha)
So, we can have Deva Vaishya, manushya Kshatirya, Rakshasa Brahmana etc.
e.g. Ravana was Rakshasa jati & Brahmana varna. Shukracharya is Deva Brahmana. Chitrangadha is Gandharva Kshatriya.
Next, both birth & character determine one's varna. Normally, either one alone is not sufficient.
e.g. Drona was brahmana but fought in Mahabharata, Koushika was kshatriya but did severe penance for thousands of years and converted into brahmana (Vishvamitra).
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