Dumingag is a 2nd class municipality in the eastern part of the province of Zamboanga del Sur. It is composed of 44 barangays, with a total land area of 618.50 square kilometers and a population of 46,039 per census in August, 2007.

Situated in the heartland of the Zamboanga peninsula and on the northwest portion of the fertile Salug Valley, Dumingag is bounded on the North by the municipality of Sergio Omeña, Sr.; on the East by the municipality of Mahayag; on the South by the municipalites of Sominot and Midsalip; and on the West by the municipality of Siayan.

Dumingag was part of the municipality of Molave when it was created into a barrio in 1950, and Jose Montuerto served as the first barrio lieutenant. On December 27, 1957 Dumingag became a municipality by virtue of Executive Order No. 283 issued by then President Carlos P. Garcia. Since its creation up to this writing, five municipal mayors have handled the reins of municipal government of Dumingag, namely: Hon. Isidoro Y. Real, Sr., 1957-1978; Hon. Julian C. Kho, 1978-1986; Hon. Domeciano E. Real, 1986-1998; Hon. Edgardo G. Jamero, 1998-2007; and Hon. Nacianceno M. Pacalioga Jr., 2007 up to the present. Hon. Isidoro Y. Real, Sr. is considered by many as the father and builder of Dumingag, he being the first and longest-serving  mayor.

Dumingag was once a vast expanse of jungle and marshland, the favorite habitat of wildlife. Its first inhabitants were the Subanens who came from coastal areas of Misamis Occidental and Zamboanga del Sur. They were forced to go farther inland by influx of Visayan settlers. How did Dumingag get its name? Some says it is named after a noted Subanen chieftain and his wife, DUMI and INGAG.

Another supposed origin of the name "Dumingag" tells about the native fellow who was asked by a government agent as to what the name of the place was while watching a cockfight. When the game was through, the stranger inquired about the name of the place. The native curtly answered: "Duminag!" (meaning "I won"). The government agent misheard the word. Instead of "Duminag", he wrote down "Dumingag".

Thus, from that time on, the place has been officially identified as Dumingag.

Today, Dumingag is gradually inscribing its name in Region IX as well as in the national level as it garnered awards and citations in different fields of endeavor. Dumingag is no longer the mountainous place in the imagination of visitors but a spacious town headed towards progress and development.