The Buddhists came to Kerala and established their temples and monasteries in different parts of the Country. The following Hindu temples were once Buddhist shrines: the Vadakkunnathan Temple of Trichur, the Kurumba Bhagavathi Temple of Cannanore, and the Durga Temple at Paruvasseri near Trichur. A large number of Buddha-images have been discovered in the coastal districts of Alleppey and Quilon; the most important Buddha-image is the famous Karumadi Kuttan near Ambalappuzha. Buddhism probably flourished for 200 years (650-850) in Kerala. The Paliyam Copper Plate of the Ay King, Varaguna (885-925 A.D.) shows that the Buddhists enjoyed some royal patronage even in the tenth century. The decline of Buddhism started in the eighth century with the arrival of the Aryan missionaries and the Brahminical religion. As mentioned earlier, the Brahmin scholars defeated Buddhist monks in debates and established the superiority of the Hindu religion. Adi Sankaracharya, the Hindu revivalist, was also responsible for the fall of Buddhism; he founded Hindu monasteries and trained Hindu priest-scholars to combat his Buddhist adversaries. Buddhism faded away gradually and completely disappeared during the reign of the Vaishnavite Kulasekharas in the eleventh century. What actually happened was that Buddhism was reabsorbed into Hinduism from which it broke away. Many Keralites, like the Ezhavas, who were most likely Buddhists once, gradually became Hindus. Buddhism has left its impact on Kerala. The images and tall rathas (cars) used in temple processions, and utsavams (fairs) are said to be Buddhist legacies. The Ayurvedic system of medical treatment is also a gift of Buddhism. Buddhists opened schools [in pallikudam and ezhuthupally. Pally is the Buddhist term for school) near their monasteries. Kerala temples show traces of Buddhist art and architecture. Amarasimha, the author of the popular Sanskrit text-book used in Kerala schools until recently, was a Buddhist. Kumaran Asan, the great Kerala poet, was influenced by the great Buddhist religion and wrote the famous, Buddhist poems: Karuna. Chandala Bhikshuki, and Sri Buddha Charitam.

In the early times of Kerala the presiding religion was that of the Dravidians. In the Dravidian religion there was not one particular edict that was followed. They had a variety of local deities and tree worship as well as ancestor worship was widely practiced. Offerings of food were the most common offerings of this time. The Dravidian religion was based on social freedom and equality and the recognition of the dignity of labour. Eventually the religions of North India entered into Kerala and became tightly settled within Kerala's borders.

Jainism was one of the first to be introduced in Kerala. The Jains who settled in Kerala made little effort to convert the Dravidians residing there. They came looking for a place where they could find an atmosphere of peace and quiet so that they could indulge in their meditation. During the 8th century A.D. Jainism in Kerala started its decline, and many of the Jains were being converted into the Hindu religion. By the 16th century Jainism was almost non-existent in Kerala. Like Buddhism in Kerala almost all of the Jains and their temples had been converted to Hinduism.

Buddhism is believed to have been introduced into Kerala during the 3rd century B.C. Like Jainism, Buddhism was allowed to flourish in the mostly Dravidian Kerala, and like Jainism Buddhism in Kerala started to decline around the 8th century A.D. Unlike Jainism, however, Buddhism left a lasting mark in the life of Kerala. Buddhism had a great influence on Malayalam literature even into the present times. Buddhism became part of the Hindu culture that had started to enwrap Kerala life and culture. Many Buddhist ceremonies and modes of worship had become part of the Hindu religion. Some of the Hindu gods are even believed to be representations of the Buddha, and even the architecture of Hindu temples was greatly influence by Buddhism in Kerala. The rise of Hinduism in Kerala is synonymous with the decline of Jainism and Buddhism in Kerala.

The Hindu religious leaders in Kerala set into motion a program to undermine the influence of Jainism and Buddhism. This was a nonviolent program that had began to take serious effect during the 8th century A.D. The most effective part of this program was the importation six eminent Hindu scholars from the North, who met with the Buddhist leaders in Kerala. As the local tradition goes they met in argument, and the Hindu scholars completely defeated the Buddhists, which allowed the Hindus to gain control over the people of Kerala. The Hindus established schools for sastric studies, and converted many of the Jain and Buddhist temples into Hindu temples. By the 12th century AD the caste system had taken control over a large portion of the state of Kerala.