Mariahu, also known as Mariyahu, is a town and nagar panchayat located in the Jaunpur district of Uttar Pradesh, India. It serves as one of the six tehsils within the district, alongside Jaunpur city, Shahganj, Machalishahar, Badlapur, and Kerakat.
The town was named by King Naun Rao, the leader of the Nanwag (Nandwak) Rajputs, during the 16th century in honor of Mandav Deo, the patron deity of the Nanwag clan. Historically, the region was ruled by the Nanwag Rajputs throughout the 16th and 17th centuries. Notable landmarks include the samadhi of Mandav dev, which is situated near the Chutka Devi temple in the eastern part of the tehsil.
The area has a history of resistance against colonial rule; Baghi Sangram Singh, a leader of the Nanwags, notably revolted against the British East India Company during the Rebellion of 1857 and achieved several victories over them.