Sati or suttee is a historical Hindu practice in which a widow sacrifices herself by sitting atop her deceased husband's funeral pyre. Although it is debated whether it received scriptural mention in early Hinduism, it has been linked to related Hindu practices in the Indo-Aryan speaking regions of India which diminished the rights of women, especially those to the inheritance of property. A cold form of sati, or the neglect and casting out of Hindu widows, has been prevalent from ancient times. Greek sources from around 300 BCE make isolated mention of sati, but it probably developed into a real fire sacrifice in the medieval era within the northwestern Rajput clans to which it initially remained limited, to become more widespread during the late medieval era.

During the early-modern Mughal period of 1526–1857, it was notably associated with elite Hindu Rajput clans in western India, marking one of the points of divergence between Hindu Rajputs and the Muslim Mughals, who banned the practice. In the early 19th century, the British East India Company, in the process of extending its rule to most of India, initially tolerated the practice; William Carey, a British Christian evangelist, noted 438 incidents within a 30-mile (48-km) radius of the capital, Calcutta, in 1803, despite its ban within Calcutta. Between 1815 and 1818 the number of incidents of sati in Bengal doubled from 378 to 839. Opposition to the practice of sati by evangelists like Carey, and by Hindu reformers such as Ram Mohan Roy ultimately led the British Governor-General of India Lord William Bentinck to enact the Bengal Sati Regulation, 1829, declaring the practice of burning or burying alive of Hindu widows to be punishable by the criminal courts. Other legislation followed, countering what the British perceived to be interrelated issues involving violence against Hindu women, including the Hindu Widows' Remarriage Act, 1856, Female Infanticide Prevention Act, 1870, and Age of Consent Act, 1891. Ram Mohan Roy observed that when women allow themselves to be consigned to the funeral pyre of a deceased husband it results not just "from religious prejudices only", but, "also from witnessing the distress in which widows of the same rank in life are involved, and the insults and slights to which they are daily subject."

Isolated incidents of sati were recorded in India in the late-20th century, leading the Indian government to promulgate the Sati (Prevention) Act, 1987, criminalising the aiding or glorifying of sati. The modern laws have proved difficult to implement; as of 2020, at least 250 sati temples existed in India in which prayer ceremonies, or pujas, were performed to glorify the avatar of a mother goddess who immolated herself on a husband's funeral pyre after hearing her father insult him; prayers were also performed to the practice of a wife immolating herself alive on a deceased husband's funeral pyre.