Southern Vietnam (Vietnamese: Nam Bộ) is one of the three geographical regions of Vietnam, the other two being Northern and Central Vietnam. It includes 2 administrative regions, which in turn are divided into 19 First Tier units, of which 17 are provinces and 2 are municipalities. In a sub-context, "Southern Vietnam" may include part of Central Vietnam. Known as Nam Bộ today in Vietnamese, it was historically called as Gia Định (1779–1832), Nam Kỳ (1832–1945), Nam Bộ (1945–48), and Nam Phần (1948–75).