After the fall of the Mahodayapuram Cheras in 12th century, Malabar Coast was fragmented into numerous feudal city states called nads (swaroopams), ruled by Naduvazhis. Moopil Nair is the term used to denote Nair Naduvazhis (rulers of nads or city states) and Desavazhis (rulers of desams) of tiny feudal kingdoms on the Malabar Coast, present day Kerala state,South India. Moopil Nairs belonged to the Samanthan Nair subcaste of the Nair caste in the Hindu Caste system.
These Nads were again divided in to desams ruled by the Desavazhis .Perumbayil Tharavadu was the desavazhis of Paluvai desam.
Perumbayil family is one of the oldest and aristocratic Nair/Menon families in Guruvayoor Area. Some of this family members were ayurveda practitioners. The most famous royal dynasty of the Moopil Nairs were Valluvakkonathiris, who ruled Valluvanad, based on present day Angadippuram. Other important royal dynasties were that of Kavalappara Moopil Nair (of Kavalappara Swaroopam), Kuthiravattathu Moopil Nair (near Kozhikode, commanded Samoothiri of Calicut's cavalry forces), Mannarkad Moopil Nayar (ruled the area in and around Attappady) and Kuppathode Moopil Nair (ruled Pulpally).