(    1720 –  1750  )

When Nana Osei Tutu was called to eternity,he was succeeded by his grand nephew, Nana Opoku Ware I . He also continue the work of his grand uncle and waged wars to extend his Kingdom. According to oral tradition, he had his own peculiar way of warfare and annexation. On his march,he would always send messengers to the chief of any state he got to ,and ask him to join him for war . If the chief agreed, he would join hands with him and give the necessary ammunition. If he refused, Nana Opoku Ware I and his army would march on him,conquer him and annex his territory to Asante Kingdom. Before his death in 1750 , he added Sefwi , Bono, and Gyaman states to the Asante Kingdom.

He fought the Akyems on two occasions and defeated them. It was during one of Nana Opoku Ware I his encounters with the Akyems that Ebirimoro, chief of Sefwi and his troops invaded Kumase and took many of the women and children as captives. And when the King heard the news he immediately dispatched Nana Amankwaatia, chief of Bantama and his troops to rescue the situation. Nana Ebirimoro and his troops were chased and beaten. Ahafo, which was their land was annexed to the Asante Kingdom.

This incident brought about the creation of Home Guard in the Asante Military buildup. This was created so that there would always be soldiers guarding the state whenever they are at war with another state. According to W.E.F  Ward, the boundaries of Asante Kingdom extended in the west to River Bia, in the north to River Tain ,in the east to River Volta and in the south to River Pra and River Tano, before the death of Nana Opoku Ware I .
The success of Nana Opoku Ware,s reign could be attributed to the following factors:

1)      That he successfully subdued internal revolts. First it was odd that a grandnephew should ascend the throne whereas the nephews of Nana Osei Tutu like Kusi Obodum who later ascended the throne after Nana Opoku Ware,s death. This might have caused some revolt among the royals but since Nana Osei Tutu had willed that the grandnephew should be enstooled, and since Nana Opoku Ware proved himself capable, he was better qualified to be the king . This initial problem of who should be the king to spurred the conquered states on to fight and crush the new Kingdom. The Akyem Kotokus took this opportunity to crush the Asante Kingdom but were defeated on two occasions. This defeat of the Akyems earned Nana Opoku Ware the papers on the three Accra Forts.

2)       That is grand uncle had expanded the Asante Kingdom spurred him on to continue with the war of expansion. It could be said that Nana Opoku Ware had the following to his credit

A)        He consolidated the foundation laid by Nana Osei Tutu by subduing internal revolt.

B).      He continued the war of expansion and annexation started by Nana Osei Tutu therefore by the end of hie reign he had tripled the length and breadth of the Kingdom.

C)       He created the Ankobea Flank or Home Guard,to women and children who would be left at home when the Kingdom was at war with another state or nation . However, he too committed the mistake of leaving conquered states to be on their own without direct interference in their internal affairs. And this again created problems for his successor, Nana Kusi Obodum.