The Benin Kingdom is an empire located in West Africa along the Niger River stretching from the Niger Delta to the Atlantic Ocean. The Benin Kingdom is the largest of the West African kingdoms. It is a home to more than 48.1 million inhabitants, the majority of which belong to the Edo ethnic group of the Niger Delta. The Benin nation itself spans a total of 2,209,450 km2 (853,073 sq mi) as of 1490. Establish in 1180, Benin was founded by the Ogisos and grew to become one of the eldest and most developed states in the Niger Delta region, as well as boasting one of the most advanced societies south of the Sahara Desert. The nation became a genuinely unified empire under Oba Ewuare in 1413, following the death of his father, Orobiru. Extensive trade and exploration of the surrounding regions, as well as the development of scientific pursuits and the arts in Benin, have since become priorities of the imperial government, seeking to expand the influence of Benin well beyond its borders. The Benin Kingdom cannot be accredited to one Oba that rules the kingdom, but a collection of Obas who strengthened the empire at different times through their unparallel leadership wisdom.