The word "Yoruba" describes both a language and a tribe which lives across Nigeria and the Popular Republic of Benin, in an area of forest and savannah. Their origins can be traced back to the end of the first millennium. The enormous scale of the slave trade in Nigeria contributed to the diaspora of the Yoruba people and informed the spiritual practices of people in countries such as Haiti, Cuba, and Brazil. Yoruba stools relate to kings and important chiefs, as do the Luba stools. The Kings and chiefs defined their power by the display of prestige objects during important ceremonies. Stools were among the most important of these objects. The ruler was literally as well as figuratively supported by a male or female caryatid figure, which also symbolizes the continuity of power. -Robbins/Nooter