The Municipality’s name came from Kapalong River, a major river that joins Maguimon River in the Sitio now called Patel. Local lore says the river got its name from “Napalongan”, Cebuano for extinguished. When a severe drought hit the riverine settlement along that river causing it to dry up, it led to scarcity of food: no fish, games, nor forage, triggering a famine that wiped the village. The locals called that place “Napallongan to otow”, meaning “people were extinguished”– literally “people died”.
Kapalong’s jurisdiction under the presidential edict was “from the intersection of Rio Biga at Latitude N-8, thence due south passing the peak of Mount Ampawid to the point of junction of the Magdagundong and Liboganon rivers; thence due west to the provincial boundary line of the provinces of Davao and Cotabato; thence in a meandering northerly direction following said boundary to its intersection with the provincial boundary line of the provinces of Davao and Agusan in the eight latitude; thence due east to the point of beginning which is at the intersection of Biga River and north latitude N-8”.
To underscore Kapalong’s status as a municipal district, it had its own judicial structure as early as 1938 following the appointment of Jose Mañgune as justice of peace of the locality who went on to become Davao city Councilor (1945-1947). In 1939, the town had a population of over 5,000.
Kapalong became a regular town under Executive Order No. 151 which President Elpidio R. Quirino signed on July 8, 1948 but took effect on August 1, 1948. Today, the municipality which has jurisdiction over an area of 84,934 hectares (from the original 188,000 hectares) is a first class town with fourteen (14) barangays.