The origins of the town is traced by historians to at least 8th-9th century AD. The Ay dynasty which acted as buffer between Pandya and Chera dynasty mainly shifting between independent rule and Pandyan overlordship.The conquest of Ay Kingdom in 765 CE by Pandya king Jatila Paranthaka/Nedum Chadayan Varaguna I (r. 765–815 AD) and sack of port Vizhinjam by defeating the Vel chieftain (the Vel Mannan, who might have been related to the Ay family) possession of the Ay-Vel country ("the fertile country along with its magnificent treasures") (Madras Museum Plates of Jatila Parantaka, 17th year). This event is also remembered in the Velvikkudi plates (3rd regnal year, Nedum Chadayan) as "the suppression of the rebellious Ay-Vel. The Pandya king "Maran Chadayan" Jatila Paranthaka destroyed a fort at Aruviyoor (Aruvikkarai near Thalakulam) by defeating Chadayan Karunanthan of "Malai Nadu" in 788 AD (23rd year, Kalukumalai inscription). In 792 AD (27th year, Jatila Paranthaka) the Chera warriors (the Cheramanar Padai) are seen fighting for a fort at Vizhinjam and at Karaikkotta (Karaikkodu near Thalakulam) against a commander of Maran Chadayan (Trivandrum Museum Inscription of Maran Chadayan).

This historical evidences points to existing Ay/Vel kings with name Chadayan (Maran Chadayan) along with the invader of the kingdom 'Nedum Chadayan' also holding a similar name. What makes this relatable to the town of Chadayamangalam is the presence of the Kottukal rock cut temple located just inside 4km from the town center. The temple is build around 8th-9th century according to archeological sources and follows the Pandyan/Ay style of architecture pronounced in other rock temples in southern Tamil Nadu and Kerala. A similar temple can be seen in Vizinjam, the capital of Ay Kingdom dated to the 8th century [10].Eventhough there are huge similarities to the Pandyan rock cut temples build at same time in core Pandyan territory, the possibility of Ay kings to have adopted the architecture cannot be left out.

This ambiguity is further strengthened as it was time of Pandyan conquest into the Ay kingdom (Pandyans continued to occupy the southern portions around Vizinjam till the next century while northern portions detached away to form Venad) and the closest town to Chadayamangalam is Ayur, which loosely translates to the town/village/place of the Ay in colloquial Malayalam and Tamil. So all this shines light on the place having a Pandyan or/and Ay patronage in antiquity with a name that derived from the name of ruler of the same area.

Chadayamangalam is 37.5 km away from the City of Kollam and 43 km away from the capital city of the state, Thiruvananthapuram. The town is located Kilimanoor and Kottarakara, 14 km away from Kilimanoor and 21 km from Kottarakara. It is situated on the southeast side of Kottarakkara Taluk. Population is of 22,213. Panchayat includes Chithra, Kadakkal, Chadayamangalam, Ittiva, Velinalloor, Elamadu & Nilamel.