The Benins Empire like other counterpart empires of old was a conglomeration of diverse kingdoms or states, peopled by ethnic groups with their diverse cultures, each of whose leadership swore fealty to the surzerainity of the Oba of Benin!
Benin rose from the status of Kingdom to an Empire, when neighbouring kingdoms were acquired either through outright military subdugation or client states alignments, gaining for her Obas, new statuses as Emperors, hence the appellation ' Uku akpolokpolo' meaning, 'King of kings', Oba no s'oba!
From then on, military campaigns against the Empires enemies now involved auxiliaries, that's military units wholly composed of non Benin speakers, that further strengthened the Benin military machine,making it formidable in size and scope! The use auxiliaries was more defined and confined, most times, to her Esan northern neighbours and the Uzon, her neighbours in south, denizens of the creeks, that are abound in her costal territories, especially in the area of ferrying large body of troops across rivers to secure military objectives in Benin naval campaigns, prompting the Benin adage "Iwemwin ese, oma gia gb'Uzon" meaning the dexterity of the Uzon spared them annihilation"! The coming of the Portuguese in the closing era of the 15 century also saw Portuguese soldiers in auxiliary roles, expecailly in the introduction and usage of ordnance which was novelle at the period, greatly giving the Empire troops, added leverage that most times, turn tide of battles in their favour! And this remained the scenario, until the unfortunate succession wars between Benin princes, contending for the exulted throne at the center, that racked the empire's seat, sanguineous conflicts that greatly weakened the empire, making her to loose grip of her very many possessions at the periphery! The impact of these negative developments was so profound that by 1897, Benin Empire had virtually become a shadow of her former greatness. An empire only in name rather than in scope!