整理自维基:With the exception of the Côn Đảo islands, all of Bà Rịa–Vũng Tàu province was once a part of Đồng Nai Province to the north. In 1979, Vũng Tàu was broken away from Đồng Nai and merged with the Côn Đảo islands (formerly part of Hậu Giang Province), forming the new Vũng Tàu–Côn Đảo “special zone”. Later, in 1992, Bà Rịa was also broken away from Ðồng Nai Province, merging with Vũng Tàu–Côn Đảo to form the modern province of Bà Rịa–Vũng Tàu.
(越南统一后)头顿市于1979年析自同奈省,昆仑岛于同年析自后江省,于1979年重组为头顿-昆岛特别区,巴地与1992年析自同奈省,加入并组成为巴地头顿省
昆仑岛原来在法国殖民时代是专门关押反殖民当局人士的著名监狱,南越地图也显示其时昆岛直辖于西贡自治市(彼时头顿为头顿自治市),所以猜测昆仑岛原来的政治地位重要(或许也有补给的因素),故挂靠于重要城市,就像东沙太平岛挂靠在高雄那样
如果有人绘制一个系列图,这个经过或许就清楚一点