Syed Ahmad Barelvi, also known as Sayyid Ahmad Shahid, (1786–1831) was an Indian Islamic revivalist, scholar, and military commander from Raebareli, a part of the historical United Provinces of Agra and Oudh. He launched the Indian jihad movement that waged a decades-long Islamic revolt against colonial rule across various provinces of British India. Sayyid Ahmad is revered as a major scholarly authority in the Ahl-i Hadith and Deobandi movements. The epithet 'Barelvi' is derived from Raebareli, his place of origin.

A mujaddid, is an Islamic term for one who brings "renewal" to the religion. According to the popular Muslim tradition, it refers to a person who appears at the turn of every century of the Islamic calendar to revitalize Islam, cleansing it of extraneous elements and restoring it to its pristine purity. In contemporary times, a mujaddid is looked upon as the greatest Muslim of a century.