Islam is the second-largest religion in South Asia, with more than 650 million Muslims living there, forming about one-third of the region's population. Islam first spread along the coastal regions of the Indian subcontinent and Sri Lanka, almost as soon as it started in the Arabian Peninsula, as the Arab traders brought it to South Asia. South Asia has the largest population of Muslims in the world, with about one-third of all Muslims living here. Islam is the dominant religion in half of the South Asian countries (Pakistan, Maldives, Bangladesh and Afghanistan). It is the second largest religion in India and third largest in Sri Lanka and Nepal.
On the Indian subcontinent, Islam first appeared in the southwestern tip of the peninsula, in today's Kerala state. Arabs traded with Malabar even before the birth of Prophet Muhammad. Native legends say that a group of Sahaba, under Malik Ibn Deenar, arrived on the Malabar Coast and preached Islam. According to that legend, the first mosque of India was built by the mandate of the last King of Chera Perumals of Makotai, who accepted Islam and received the name Tajudheen during the lifetime of the Islamic prophet Muhammad (c. 570–632). On a similar note, Malabar Muslims on the western coast also claim that they converted to Islam in Muhammad's lifetime. According to Qissat Shakarwati Farmad, the Masjids at Kodungallur, Kollam, Madayi, Barkur, Mangalore, Kasaragod, Kannur, Dharmadam, Panthalayini, and Chaliyam, were built during the era of Malik Dinar, and they are among the oldest Masjids (mosques) in the Indian Subcontinent. Historicaly, the Barwada Mosque in Ghogha, Gujarat built before 623 CE, Cheraman Juma Mosque (629 CE) in Methala, Kerala and Palaiya Jumma Palli (630 CE) in Kilakarai, Tamil Nadu are three of the first mosques in South Asia.
