[2][5] Quezon City was the designated regional center of Southern Tagalog,[1] but Lucena was the former Government Center of Southern Tagalog, and is still host to most of the branches of governmental agencies, businesses, banks, and service facilities in the region.

One obvious reason for creating the sub-province was the area's isolation from the rest of Quezon Province: there were no direct links to the rest of the province and much of the terrain was mountainous and heavily forested, which made the area relatively isolated, and its distance from Quezon's capital Lucena.

[3][4] The complete separation of Aurora from Quezon and its transfer to Central Luzon fulfilled the long-held wishes and prayers of the residents of the original municipalities of Baler and Casiguran, allowing them to be truly independent from Quezon Province for the first time and to restore the original La Pampanga from the Spanish era.

[14] Camarines Norte and Camarines Sur, which are under Bicol Region, are sometimes considered part of Southern Tagalog recently, as there has been a language shift in recent years to Tagalog, which is more common native language, from being historically Bikol-speaking provinces.

The languages not native to the region are: Ilocano in Quezon, Laguna, Rizal, Cavite, Batangas, Mindoro, and Palawan (Aurora & Quezon have the largest concentration of Ilocano speakers when Aurora was part of Southern Tagalog, the statistics now exclusively belong to Quezon); Bikol in Quezon, Batangas, Cavite, Laguna, Rizal, and Marinduque; Cebuano in Rizal, Batangas, Cavite, and Quezon (especially in the remote parts of San Andres and San Francisco, the southernmost municipalities both located in the Bondoc Peninsula); Kapampangan and Pangasinan in Batangas, Cavite, Mindoro and Palawan; Maranao and Maguindanaon in many parts of the region especially in urban areas.