The history of asylums in India provides an opportunity to study the spread of ideas about mental illness, and notions of care and responsibility for the mentally ill across cultures and time. Although there are suggestions that hospitals have been known in the south Asian region from antiquity, there is little documentary proof of their existence. References for institutions for the sick and needy can be found during the reign of Ashoka (268–231 BC). Travellers' accounts of AD 400 mention similar services established by rich merchants and nobility. Mental hospitals had a long history in the Arab world, and the growing Muslim influence in India lead to the establishing of similar hospitals. However, the prevailing social situations have led some authors to suggest that these were seldom used except by ‘soldiers and foreigners’. Medical care in medieval India was based on Ayurvedic (derived from the Charak Samhita and other classical Indian and largely pre-Islamic texts, thus predominantly Hindu) and Unani (the Muslim school of medicine), and derivative systems, delivered by professionals trained by study and apprenticeship. These professionals were most often attached to the court, or provided services for a fee. Religious and caste divisions perhaps did not allow a public space for uniform treatment for the ill to exist.