About the middle of the 7th century A.D. Buddhism was in a state of decline. Its final defeat is attributed to Kumarila Batta and Sankaracharya. Kumarila was the founder of the Bhattapada school of Karma-mimamsa and was a great opponent of Buddhism. For his hand, he took the Vedas and vedik rites as the basis. Sankara who lived in the later part of the 8th century and the earlier part of the 9th century completed the work started by Kumarila, and much more.
Sankara assimilated some of the good points of Buddhism. Never deploring the Vedik rites and rituals , he purified them by removing those parts which are misused. He erected the edifice of Advaita and established four monasteries as centres of religious teaching and missionary work. These mathas,to this date, are the sources of light and wisdom to millions of Hindus.