The settlement of Koronadal and its creation as a municipality by virtue of Executive Order No. 82 dated August 18, 1947 was marked by a rapid initial development, so that when the province of South Cotabato was created under Republic Act No. 4849 on July 18, 1966, it easily became the capital town. In the past, the place was populated by B'laans and Maguindanaos. The word Koronadal is believed to have been derived from two B'laan words- koron or kolon meaning cogon grass and nadal or datal meaning plain which optly described the place to the natives. On the other hand, Marbel, which is another name for the poblacion, is a B'laan term "Marb-El" which means "murky waters" (it is possible that name was first used to) referring to a river, now called Marbel River. Koronadal used to comprise the area extending from the banks of Buluan Lake to the north to Barangay Polonoling in the municipality of Tupi to the south from Quezon mountain range to the northeast to the municipality of T'Boli to the southeast. It was in August 18, 1947 when President Manuel Roxas signed the Executive Order creating the municipalities in the entire province of South Cotabato, one of which was Koronadal. The same executive order likewise mandated the official function of the municipal government which began after the qualification and election of the first set of municipal officials. Elected were Datu Kudanding Kamsa, Municipal Mayor, Perfecto Sueno Sr., Vice Mayor; Councilors: Porferio Cuenca, Felix Suscano, Alejandro Poticar, Gregorio Hechanova, Zacarias Cadule, and Dencio Sarate. The first Municipal Judge was Braulio Hurtado and the first Health Officer was Dr. Felimon de Jesus, Cornelio Mariveles became the Chief of Police and Godofredo Gazo, the Municipal Secretary.

The municipal government of Koronadal began its official function on January 1, 1948 with an approved Annual Estimated Budget of P30,000.00. The land area of the municipality by then was comparable with the Province of Bata-an embracing the present municipalities of Tampakan, Tupi, Banga, Lake Sebu, Surallah, T'Boli, Sto. Niño, Norala, and Isulan. Municipal Council Resolution No. 32, Series of 1948 mandated and proclaimed January 10 of each year as the Municipal Town Fiesta commemorating the foundation of Marbel Settlement District of the National Land Settlement Koronadal was converted into a component city of South Cotabato now known as the City of Koronadal by virtue of Republic Act 8803 on October 8, 2000. At present, Koronadal is a fast developing growth center composed of twenty seven (27) barangays including the four (4) zones in the poblacion. Being the capital town of South Cotabato, it is the center of the province in terms of political, cultural and socio-economic activities. Business firms and other establishments sprout in Koronadal. Identified also as the Provincial Agri-industrial Center of South Cotabato. Koronadal boasts of its favorable geographical location, rich human and natural resources, and potentials conducive for trade business and industry. Marbel Settlement District of the National Land Settlement.