Nawab is a Royal title indicating a sovereign ruler, often of a South Asian state, in many ways comparable to the western titles of King. The relationship of a Nawab to the Emperor of India has been compared to that of the Kings of Saxony to the German Emperor.

In earlier times the title was ratified and bestowed by the reigning Mughal emperor to semi-autonomous Muslim rulers of subdivisions or princely states in the Indian subcontinent loyal to the Mughal Empire e.g. Nawabs of Bengal. The title is common among Muslim rulers of South Asia as an equivalent to the title Maharaja.

"Nawab" usually refers to males and literally means "Viceroy"; the female equivalent is "Begum" or "Nawab Begum". The primary duty of a Nawab was to uphold the sovereignty of the Mughal emperor along with the administration of a certain province.

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