Operating from their "illam" houses, Nambudiris' ownership of agricultural land under the janmi system increased over many centuries and, according to Moser and Younger, they "established landholding temples and taught the people the rules of caste". The Nambudiris have been described to be responsible for the Sanskrit influence on Malayalam, basically a Dravidian language, due to the Nambudiri Brahmin's mixing of Sanskrit and the local Tamil language.