The Igala state with its capital in Idah, flourished on the bank of the Niger just below its confluence. The early history of the people before 1800 is obscure. The major themes in the evolution of the Igala state are preserved in legend associated with specific personalities. There is the legend dealing with the trader of sovereignty from an aboriginal population (the okpoto) to a foreigner usually identified as abutu Eje sometimes identified as a child reared by a leopard (Eje) or as a prince from Ado (Benin), or Apa (Wukari Jukun). Another legend speaks of the emergence of one Achadu from the Igbo country whose personal attribute facilitated his marriage to the female Attached, and who by development, became a patron (ritual husband) and the leader of the kingmaker (igalla-Mela). There also exist legends which suggest that the Igala are of a Yoruba extraction. Other traditions speak of a period of Jukun overrule.
what is clear from the available evidence is that the Igala state was already in existence by the late fifteenth century. Benin traditions make a clear reference to the kingdom in the late fifteenth century. The Portuguese upon their arrival in Benin were asked to assist the Oba in a war against the king of Idah.
Prior to the foundation of the present dynasty from the Jukun capital in the seventeenth century, earlier dynasties seem to have been strongly influenced by their contact with the Yoruba and Edo. Historical evidence exist to show that the territories of the Igala and some Yoruba speaking peoples had been once contiguous. Surviving features of such a period include the existence of settlements of Igalaspeaking peoples on the right or west bank of the Niger such as Ajaokuta and Geregu.
At the peak of its power, the Igala state commanded the right bank of the Niger from its confluence southward to a point just above Onitsha and the south bank of the Benue from its confluence with the Niger far up, to a hundred kilometres. The ultimate extent of the area inhabited by the Igala on the west bank, prior to the coming of other groups like the Igbirra and Bassa is Open to conjecture but a community like the isolated Igalla speaking village of Ebu near Asaba in present day Delta State, presents an interesting case of its expansion dynamics.
The Igala exercised some authority over the Igbo speaking peoples to its south and over the Igbirra and Kankande north of the confluence. The foundation of the present dynasty is credited to Ayagba or Idoko, the ancestor to all subsequent Attahs. It was he who broke up the tribtitary with the Jukun. For the I galla of the pre-dynastic period, in the political structure was such that the supreme authority of state vested the [gala Mela each of whom like the Uzama Nihiron of Benin, or the Oyomesi of the Y oruba, had territories to administer. In pre-dynastic times, the Igalla Mela was the administrative head of his kingdom. The real significance of the Igala Mela in the evolution of the Igala state is that they formed a government with a defined territory in the Idah area. Later, a foreigner was received in circumstances not very clear who ruled over the 'moieties' of the Igala Mela. With Idah as its core centre, the adjacent territory of 'Okpoto' was incorporated under the rule of the Attahs like Ayagba and his successors to form the mega state that I galla became and as is understood today. Not much is known aboutAyagba’s successors before 1800.
The Igalla were principally agriculturists. They also did some fishing on the rivers of the Niger and Benue. The political structure was Operated on two levels. There was a central and provincial level of administration. The Attah was head of the centre and was assisted by a council of chiefs and other officials who helped in the local or provincial administration of the kingdom.