An kafa tsohuwar Jihar Yammacin Najeriya a shekara ta 1967 lokacin da aka raba yankin Yamma zuwa jihohin Legas da Yammacin ƙasar. Babban birninta shine Ibadan, wanda shine babban birnin tsohon yanki. A shekara ta 1980 an raba jihar zuwa sabbin jihohi uku, Ogun, Ondo da Oyo . Yankin yanzu ya ƙunshi jihohi tara, a yankuna uku na geopolitical : Delta, Edo, Ekiti, Kwara, Lagos, Ogun, Ondo, Osun, and Oyo States . Jihar Oyo ita ce jiha mafi girma a yankin Kudu maso Yamma . Ya mamaye fadin ƙasa 28,454km2. Ana iya cewa Legas ita ce jiha mafi shahara da mutane sama da miliyan 20 ke zaune a cikinta. 18-1900s ƙasar Yarbawa "Western states in Nigeria and all about them". Nigerian Finder.