Southern Tagalog, or Region IV, was a region of the Philippines that is now comprised of Region IV-A (CALABARZON) and Region IV-B (MIMAROPA). Region IV was split into the two regions on May 17, 2002. Before the split, Southern Tagalog was the largest region in terms of both population and area.
Southern Tagalog comprises the provinces of Aurora, Batangas, Cavite, Laguna, Marinduque, Oriental Mindoro, Occidental Mindoro, Palawan, Quezon, Rizal, and Romblon. Quezon City was the designated regional center of Southern Tagalog.
Southern Tagalog covers the area where many Tagalog native speakers reside. The new capital region also known as NCR of Metro Manila and Central Luzon are the other regions of native Tagalog speakers. In this respect, Central Luzon can be considered as the Northern Tagalog region.
