Region IX (Zamboanga Peninsula)

PSGC: 090000000
ISO: 09
Regional Centre: Pagadian City
Congressional Districts: 9
Provinces: 3
Cities: 5 *
Municipalities: 67
Barangays: 1,904 *

September 24, 1972: Region IX (Western Mindanao) created from Sulu, Zamboanga del Norte and Zamboanga del Sur with Jolo as the regional centre, by Presidential Decree No. 1 as part of the Integrated Reorganisation Plan.
July 7, 1975: Zamboanga del Norte removed from Region IX by Presidential Decree No. 742.
August 21, 1975: Region IX reorganised and Sub-Region IX-A created from Basilan, Sulu and Tawi-Tawi with Jolo as the regional and sub-regional centre, and, Sub-Region IX-B created from Zamboanga del Norte and Zamboanga del Sur with Zamboanga City as the sub-regional centre, by Presidential Decree No. 773.
June 11, 1978: Zamboanga City designated as the regional centre by Presidential Decree No. 1555.
July 25, 1979: Region IX established as an autonomous region by Presidential Decree No. 1618 in accordance to the Tripoli Agreement of December 23, 1976.
August 1, 1989: Sulu and Tawi-Tawi removed from Region IX by Republic Act No. 6734. Ceased to be an autonomous region.
October 12, 1990: Lanao del Norte, Misamis Occidental and Marawi City transferred to Region IX, and, Pagadian City designated as the regional centre by Executive Order No. 429, but not executed.
September 19, 2001: Region IX renamed Region IX (Zamboanga Peninsula) and Basilan, excluding Isabela, City of, removed from Region IX by Executive Order No. 36.
November 12, 2004: Designation of Pagadian City as regional centre by Executive Order No. 429 executed by Memorandum Circular No. 75.

* Including Isabela, City of.

PSGC: 097200000
ISO: ZAN
Province Capital: Dipolog City
Area Code: 65
Congressional Districts: 3
Cities: 2
Municipalities: 25
Barangays: 691

June 6, 1952: Zamboanga del Norte province created from Zamboanga by Republic Act No.711.

PSGC: 097300000
ISO: ZAS
Province Capital: Pagadian City
Area Code: 62
Congressional Districts: 4
Cities: 2
Municipalities: 26
Barangays: 779

1837: Zamboanga created as a district.
1860: Zamboanga district reorganised.
May 18, 1899: Zamboanga Republic established.
October 30, 1899: Military District of Mindanao and Jolo created from Cotabato, Davao, Lanao, Misamis, Surigao, Sulu and Zamboanga.
November 16, 1899: Zamboanga Republic abolished.
April 24, 1900: Military Department of Mindanao and Jolo created from the Military District of Mindanao and Jolo and Palawan.
July 15, 1903: Moro Province created from Cotabato, Davao, Lanao, Sulu and Zamboanga by Act No. 787.
December 20, 1913: Moro Province renamed Department of Mindanao and Sulu by Act No. 2309.
July 23, 1914: Zamboanga province created from the Department of Mindanao and Sulu.
March 10, 1917: Zamboanga province established by Act No. 2711.
February 5, 1920: Department of Mindanao and Sulu abolished by Act No. 2878.
June 6, 1952: Zamboanga del Sur province created from Zamboanga by Republic Act No.711.

PSGC: 098300000
ISO: ZSI
Province Capital: Ipil
Area Code: 62
Congressional Districts: 2
Cities: 0
Municipalities: 16
Barangays: 389

February 22, 2001: Zamboanga Sibugay province created from Zamboanga del Sur by Republic Act No. 8973.