As of the 7th century BCE the African peoples who lived in Yorubaland were not initially known as the Yoruba, although they shared a common ethnicity and language group. By the 8th century, a powerful kingdom already existed in Ile-Ife, one of the earliest in Africa. It is said to be Ile-gbo (capital of the realm of humanity, based on the oldest predynastic traditions of its being associated with Oba Tala, Oro-gbo (Shango) and Otete (Oduduwa) .
The historical Yoruba develop in situ, out of earlier Mesolithic Volta-Niger populations, by the 1st millennium BCE. Oral history recorded under the Oyo Empire derives the Yoruba as an ethnic group from the population of the older kingdom of Ile-Ife. The Yoruba were the dominant cultural force in southern and Northern, Eastern Nigeria as far back as the 11th century.
The Yoruba are among the most urbanized people in Africa. For centuries before the arrival of the British colonial administration most Yoruba already lived in well structured urban centres organized around powerful city-states (Ìlú) centred around the residence of the Oba. In ancient times, most of these cities were fortresses, with high walls and gates.Yoruba cities have always been among the most populous in Africa. Archaeological findings indicate that Òyó-Ilé or Katunga, capital of the Yoruba empire of Oyo (fl. between the 11th and 19th centuries CE), had a population of over 100,000 people.For a long time also, Ibadan, one of the major Yoruba cities and founded in the 1800s, was the largest city in the whole of Sub Saharan Africa. Today, Lagos (Yoruba: Èkó), another major Yoruba city, with a population of over twenty million, remains the largest on the African continent.
Archaeologically, the settlement of Ile-Ife showed features of urbanism in the 12th–14th century era. In the period around 1300 CE the artists at Ile-Ife developed a refined and naturalistic sculptural tradition in terracotta, stone and copper alloy – copper, brass, and bronze many of which appear to have been created under the patronage of King Obalufon II, the man who today is identified as the Yoruba patron deity of brass casting, weaving and regalia. The dynasty of kings at Ile-Ife, which is regarded by the Yoruba as the place of origin of human civilization, remains intact to this day. The urban phase of Ile-Ife before the rise of Oyo, c. 1100–1600, a significant peak of political centralization in the 12th century,is commonly described as a "golden age" of Ile-Ife. The oba or ruler of Ile-Ife is referred to as the Ooni of Ife.
Ife continues to be seen as the "Spiritual Homeland" of the Yoruba. The city was surpassed by the Oyo Empire as the dominant Yoruba military and political power in the 11th century.The Oyo Empire under its oba, known as the Alaafin of Oyo, was active in the African slave trade during the 18th century. The Yoruba often demanded slaves as a form of tribute of subject populations,who in turn sometimes made war on other peoples to capture the required slaves. Part of the slaves sold by the Oyo Empire entered the Atlantic slave trade.Most of the city states were controlled by Obas (or royal sovereigns with various individual titles) and councils made up of Oloyes, recognised leaders of royal, noble and, often, even common descent, who joined them in ruling over the kingdoms through a series of guilds and cults. Different states saw differing ratios of power between the kingships and the chiefs' councils. Some, such as Oyo, had powerful, autocratic monarchs with almost total control, while in others such as the Ijebu city-states, the senatorial councils held more influence and the power of the ruler or Ọba, referred to as the Awujale of Ijebuland, was more limited.In more recent decades, Lagos has risen to be the most prominent city of the Yoruba people and Yoruba cultural and economic influence. Noteworthy among the developments of Lagos were uniquely styled architecture introduced by returning Yoruba communities from Brazil and Cuba known as Amaros/Agudas.
Yoruba settlements are often described as primarily one or more of the main social groupings called "generations":
*The "first generation" includes towns and citiesknown as original capitals of founding Yoruba kingdoms or states.
*The "second generation" consists of settlements created by conquest.
*The "third generation" consists of villages and municipalities that emerged following the internecine wars of the 19th century.
Reference:Johnson, Samuel (1997). The History of the Yorubas