The name of Zamboanga is the Hispanicized spelling of the Sinama term for “mooring place” – samboangan (also spelled sambuangan; and in Subanen, sembwangan), from the root word samboang (“mooring pole”). “Samboangan” was the original name of Zamboanga City, from where the name of the peninsula is derived from. “Samboangan” is well-attested in Spanish, British, French, German, and American historical records from as far back as the 17th century.
This is commonly contested by folk etymologies which instead attribute the name of Zamboanga to the Indonesian word jambangan (claimed to mean “place of flowers”, but actually means “pot” or “bowl”), usually with claims that all ethnic groups in Zamboanga were “Malays“. However, this name has never been attested in any historical records prior to the 1960s.
The original inhabitants of the Zamboanga peninsula were the Subanen, who settled along the riverbanks in inland areas; and the various Sama-Bajau and Yakan ethnic groups who settled in coastal areas. Tausūg settlers from northeastern Mindanao also migrated to the region in the 13th century.
The region was additionally settled by migrants (mostly from the Visayas islands) after World War II. Together with the original settlers, these pioneers helped develop Zamboanga del Sur into the abundant and culturally diverse province that it is.
Historically, Zamboanga was the capital of the Moro Province in western Mindanao, which comprised five districts: Cotabato, Davao, Sulu, Lanao, and Zamboanga. In 1940, these districts became individual provinces. Zamboanga City became the capital of Zamboanga province. Soon after World War II, the provincial capital was transferred to Dipolog. Molave was created as the provincial capital in 1948.
On June 6, 1952, through Republic Act 711, Zamboanga del Sur was carved out from the former Zamboanga province that encompassed the entire peninsula in southwestern Mindanao. As the 52nd province of the Philippines, it originally consisted of 11 towns, which were later expanded into 42 municipalities and one city, Pagadian, its capital.
Political developments in February 2001 saw another major change in the territorial jurisdiction of Zamboanga del Sur. Its inhabitants voted to create a new province out of the third congressional district, named Zamboanga Sibugay.