“Mandih’’, got its name from a community Subanen Leader Surname Mandih. Barangay Mandih was created on December 22, 1936. Barangays Benigno Aquino Jr. and Datu Tangkilan was once a part of this barangay. Barangay Mandih is located on southern part of Sindangan Bay bounded on the south, on the west Barangay Inuman, east by barangay Dicoyong, and Barangay Labakid on the north.

From the very beginning to the present, the Barrio's lieutenants/captains have been: Datu Agdino B. Andus, Adela de Mesa (1962–1966); Bartolome Tobias Sr. (1966–1986); Vicente Orbase Jr. (1986–1989) OIC; Wilfredo Gom-os Sr. (re-elected 1989–2002); Marcelo Andus (re-elected in 2002–2007); Nelson C.

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The former Chieftains or Timoay Pangendelan was Bonut, Taod, Conse, Amandag, Gumacial, Andus, Mandih and Caindug. Datu Tangkilan Andus son of Subanen Leader Andus, a brother of Mandih; proclaimed DATU by President Manuel L. Quezon for the subanens of the Province of Zamboanga del Norte; very first illiterate Filipino who made the irrigation canal for the rice fields farmers of Barangay Mandih and now Barangay Datu Tangkilan respectively which until now existed and being improved by the help of USAID and LGU of Sindangan.(Datu Tangkilan Andus Service Irrigators Association -DTISA)

Barangay Mandih is one of the largest and most populated amongst 52 barangays of the Municipality of Sindangan and in terms of Internal Revenue Allotment (IRA).