Littoral South Asia in the context of "Island South Asia"

South Asia is the southern subregion of Asia that is defined in both geographical and ethnic-cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's population. As commonly conceptualised, the modern states of South Asia include Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka, with Afghanistan also often included, which may otherwise be classified as part of Central Asia. South Asia borders East Asia to the northeast, Central Asia to the northwest, West Asia to the west and Southeast Asia to the east. Apart from Southeast Asia, Maritime South Asia is the only subregion of Asia that lies partly within the Southern Hemisphere. The British Indian Ocean Territory and two out of 26 atolls of the Maldives in South Asia lie entirely within the Southern Hemisphere. Topographically, it is dominated by the Indian subcontinent and is bounded by the Indian Ocean in the south, and the Himalayas, Karakoram, and Pamir Mountains in the north.

Settled life emerged on the Indian subcontinent in the western margins of the Indus River Basin 9,000 years ago, evolving gradually into the Indus Valley Civilisation of the third millennium BCE. By 1200 BCE, an archaic form of Sanskrit, an Indo-European language, had diffused into India from the northwest, with the Dravidian languages being supplanted in the northern and western regions. By 400 BCE, stratification and exclusion by caste had emerged within Hinduism, and Buddhism and Jainism had arisen, proclaiming social orders unlinked to heredity.

The String of Pearls is a geopolitical hypothesis proposed by United States political researchers in 2004. The term refers to the network of Chinese military and commercial facilities and relationships along its sea lines of communication which extend from the Chinese mainland to Port Sudan in the Horn of Africa. The sea lines run through several major maritime choke points such as the Strait of Mandeb, the Strait of Malacca, the Strait of Hormuz, and the Lombok Strait as well as other strategic maritime centres in Somalia and the littoral South Asian countries of Pakistan, Sri Lanka, Bangladesh, and the Maldives.

Many commentators in India believe this plan, together with the China–Pakistan Economic Corridor and other parts of China's Belt and Road Initiative under Chinese Communist Party general secretary Xi Jinping, is a threat to India's national security. Such a system would encircle India and threaten its power projection, trade, and potentially territorial integrity. Furthermore, China's support for India's traditional enemy of Pakistan and its Gwadar Port is viewed as a threat, compounded by fears that China may develop an overseas naval military base in Gwadar, which could allow China to conduct expeditionary warfare in the Indian Ocean Region. From the east, the deep-water port of Kyaukpyu is also viewed with a similar concern. The first comprehensive academic analyses of Chinese plan and its security implications for New Delhi was undertaken in February 2008 by an active-duty Indian naval officer. Antedating China's anti-piracy naval deployment in the Indian Ocean beginning in December 2008, and the ensuing acquisition of its first overseas military base in Djibouti in August 2017, his analysis predicting China's "permanent military presence" in the Indian Ocean is viewed by Indian policymakers as prescient. Accordingly, India has since been making moves of various types to counter the threat.