The Esan who presently inhabit four local government areas of Edo State, Nigeria, share an exclusive feeling of being one people. In language and custom they are akin to the Edo people of Benin. The name “Esan” is an Edo word meaning “jump” or “flee,” which explains the manner in which they departed the Benin kingdom. The Esan region is divided roughly into the plateau—about one-third the total area but containing three-fifths of the people—and the lowlands. The plateau chiefdoms, originally seven of them, have been classed as Esan ‘A’ and include Irrua, Ekpoma, Uromi, Ewu, Ubiaja, Udo, and Ugboha. The lowland chief doms, originally eight, are known as Esan ‘B’ and consist of Ewohimi (Orikhimi), Ohordua, Emu, Ebelle, Okalo, Amahor, Ezen, and Okaigun.
According to Esan traditions all the ancestors of the people, royal and commoner alike, came from Benin, the first groups being escapees and pioneers, the royal groups coming into the region later, during the reign of Ewuare, ca. 1455-82. Closer interviewing of clans, neither royal nor holding titles, demonstrates that many do not hold to this popular tradition, claiming either to be indigenous or to have migrated from elsewhere. Even in the intelligence report on the Esan, a significant number of clans reported origins other than in Benin. It seems that Esan ‘A’ chiefdoms on the plateau were the earliest established, and paid tribute to Benin through the Onojie (chief) of Irrua, who was therefore roughly the paramount of the Esan province of Benin. As the chiefdoms grew in numbers and spread on to the lowlands, he remained their overlord or governor. However, by the early nineteenth century the Oba of Benin installed the chief of Ewohimi as paramount over the lowland or Esan ‘B’ chiefdoms. By the advent of the British in the 1890s the earliest fifteen chiefdoms had grown to thirty.