historians assume that the Mappilas can be considered as the first native, settled Muslim community in South Asia. The inhibitions, caused by a series of Chera-Chola wars in the 11th century, resulted in the decline of foreign trade in Kerala ports. In addition, Portuguese invasions in the 15th century caused two major religions, Buddhism and Jainism, to disappear from the land. It is known that the Menons in the Malabar region of Kerala were originally strong believers of Jainism. The social system became fractured with divisions on caste lines. The Kulasekhara dynasty was finally subjugated in 1102 by the combined attack of the Pandyas and Cholas. However, in the 14th century, Ravi Varma Kulashekhara (1299–1314) of the southern Venad kingdom was able to establish a short-lived supremacy over southern India. After his death, in the absence of strong central power, the state was fractured into about thirty small warring principalities under Nair Chieftains; the most powerful of them were the kingdom of Samuthiri in the north, Venad in the south and Kochi in the middle. The port at Kozhikode held the superior economic and political position in Kerala, while Kollam (Quilon), Kochi, and Kannur (Cannanore) were commercially confined to secondary roles. The Rise of Advaita Adi Shankara (CE 789), one of the greatest Indian philosophers, is believed to be born in Kaladi in Kerala, and consolidated the doctrine of advaita vedānta. Shankara travelled across the Indian subcontinent to propagate his philosophy through discourses and debates with other thinkers. He is reputed to have founded four mathas ("monasteries"), which helped in the historical development, revival and spread of Advaita Vedanta. Adi Shankara is believed to be the organiser of the Dashanami monastic order and the founder of the Shanmata tradition of worship. His works in Sanskrit concern themselves with establishing the doctrine of advaita (nondualism). He also established the importance of monastic life as sanctioned in the Upanishads and Brahma Sutra, in a time when the Mimamsa school established strict ritualism and ridiculed monasticism. Shankara represented his works as elaborating on ideas found in the Upanishads, and he wrote copious commentaries on the Vedic canon (Brahma Sutra, principal upanishads and Bhagavad Gita) in support of his thesis. The main opponent in his work is the Mimamsa school of thought, though he also offers arguments against the views of some other schools like Samkhya and certain schools of Buddhism. His activities in