Legislative district of Zamboanga

The Legislative district of Zamboanga was the representation of the historical province of Zamboanga in the of the Philippines until 1953. The undivided province's representation encompassed the present-day provinces of Basilan, Zamboanga del Norte, Zamboanga del Sur and Zamboanga Sibugay, and the chartered city of Zamboanga.

Initially being excluded from representation in the lower house of the Philippine Legislature in 1907, the then-non-Christian-majority areas of the Philippines — which included the Department of Mindanao and Sulu, of which Zamboanga was part — were finally extended legislative representation with the passage of the Philippine Autonomy Act in 1916 by the United States Congress. The Revised Administrative Code (Act No. 2711) enacted on 10 March 1917 further elaborated on the manner by which these areas would be represented. The non-Christian areas were to be collectively represented in the upper house's 12th senatorial district by two senators, both appointed by the Governor-General. Five assembly members, also appointed by the Governor-General, were to represent the seven component provinces of Department of Mindanao and Sulu — Agusan, Bukidnon, Cotabato, Davao, Lanao, Sulu and Zamboanga — in the lower house as a single at-large district. These arrangements remained in place despite the abolition of the Department in 1920.

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