There are many legends to tell about Karunagappally Padaanayarkulangara Mahadeva Temple. Prominent among these are; It beileve that Shiva and Krishna were going through this passageway. They were tired of walking and reached this Karunagappally which was formerly forested. Lord Krishna was sent to find the best place to stay. Lord Krishna invented the place but established himself there by the beauty of the place. It was only when Mahadevan was waiting for a long time that he was sent to find the place and come back. After searching a long time, Lord Shiva found that Krishna was sitting a beautiful place and he also like to sit next to him.
Karunagappally was a part of the Ay dynasty and later became part of Odanad and then Travancore. The headquarters of the Kayamkulam kings was in Karunagappally for some time. The Pattanayarkulangara Temple, which was a Buddhist temple at that time, was converted into a Hindu temple. Many places in Kerala, formerly known as Palli, were former Buddhist shrines or their monasteries.A Buddha statue, dated to the 9th century, was recovered from Marathurkulangara in Taluk.