Among the state's fauna are mona monkey, common kestrel, purple heron, and royal antelope, along with some of Nigeria's last remaining Nigeria-Cameroon chimpanzee and African forest elephant which inhabit the heavily threatened forests along the southern borders with Ondo and Ogun states.

[8][9][10] Osun State is primarily inhabited by the Yoruba people, mainly of the Ibolo, Ifẹ, Igbomina, Ijesha, and Oyo subgroups.

Economically, Osun State is largely based around agriculture, mainly of cocoa, cassava, millet, maize, potato and yam crops.

The university is located in the ancient town of Ile-Ifẹ, an important early center of political and religious development for Yoruba culture.

Other important cities and towns include the ancient kingdom-capitals of Ila Orangun, Iragbiji, Ada, Ikirun, Oke-Ila Orangun, Ipetu-Ijesha, Ijebu-Jesa, Erin Oke, Ipetumodu, Ede, Iwo, Ejigbo, Ibokun, Ode-Omu, Otan Ayegbaju, Ifetedo, Esa-Oke, Ilesa, Okuku, Otan-Ile and Igbajo.

[16] Every year, adherents and non-adherents of Osun, one of the Orisa (the traditional deities of the Yoruba people), travel from all over the world to attend the annual Osun-Osogbo festival in August.

[17] Ọsun-Ọsogbo Grove, the shrine of the annual rites of the deity and an important artistic center, was declared a World Heritage Site in 2005.

[22] Located at an elevation of 266.33 meters (873.79 feet) above sea level, Osun has a Tropical wet and dry or savanna climate (Classification: Aw).

Osun typically receives about 127.75 millimeters (5.03 inches) of precipitation and has 237.62 rainy days (65.1% of the time) annually.

[27] Among the famous religious leaders from Osun State is the London-based Muslim cleric Sheikh Dr. Abu-Abdullah Adelabu, who hails from the state's capital city, Osogbo and Pastor (Dr.) Johnson Ade Odewale of Christ Apostolic church, Calvary Assembly from Odeomu, who is based in Boston, USA.

[28] The major traditional rulers in Osun State acclaim either the Faith of Islam or Christianity.

[30] 2.2% Catholic in the Diocese of Osogbo (1995) with 74,440 followers in 56 parishes under Bishop John Akinkunmi Oyejola (2016), a suffragan of the Archdiocese of Ibadan.

Railways: Osogbo is on the 1067 mm Cape Gauge the Western Line north from Lagos to Kano.