South India lies in the peninsular Deccan Plateau and is bounded by the Arabian Sea in the west, the Indian Ocean in the south and the Bay of Bengal in the east. The geography of the region is diverse, encompassing two mountain ranges, the Western and Eastern Ghats, and a plateau heartland. The Godavari, Krishna, Tungabhadra, Kaveri, and Vaigai rivers are important non-perennial sources of water. Bangalore, Chennai and Hyderabad are the largest and most industrialised cities in the region.
A majority of Indians from the southern region speak one of the languages: Tamil, Telugu, Kannada, Malayalam. During its history, a number of dynastic kingdoms ruled over parts of South India whose invasions across southern and southeastern Asia impacted the history and cultures of modern sovereign states such as Sri Lanka, Singapore, the Philippines, Indonesia, Thailand and Malaysia. The region was colonised by Britain and gradually incorporated into the British Empire.