In the late 1860s Charles Darwin began collecting photographs of people with mental illness, many sent by the neurologist James Crichton-Browne, who directed the West Riding Lunatic Asylum in Wakefield. Darwin wanted images of facial expressions for his theory that emotional displays were shaped by evolution, and he found that photographs of actors posing were often unreliable. Patients who could not conform to social norms seemed to show more authentic emotion, so the images were valuable to him. The correspondence between the two men lasted nearly six years and covered topics such as blushing and the bristling of hair. The studies fed into The Expression of the Emotions in Man and Animals (1872), widely regarded as the first English-language scientific book to use photographs.

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.