In 1897, the British sacked the Benin Empire, effectively leaving the Esans free from British rule. In 1899, the British led an invasion into the Esan kingdoms that lasted for seven years. Esanland proved to be harder to conquer than the Benin Kingdom because of its strong autonomy: Kingdoms chose to keep fighting the British even if its neighbors fell. Fallen Benin chiefs like Ologbosere and Ebohon were still resistant to British rule inadvertently guarded Esan soil from the west, by establishing military camps and blocking roads. This lasted from 1897 to April 22. 1899, where Ologbosere surrendered at the border village of Okemue.
The first kingdom to be attacked by the British was the Kingdom of Ekpon. Ekpon launched a fierce resistance against the British invasion on April 22, which nearly destroyed the kingdom. After the near genocide of Esans at Ekpon, the kingdom of Ekpon led an ambush of the British camp at Okueme, on April 29. This led British forces to retreat, consolidate their power, and kill Ologbosere in May. Subsequent attempts by the British failed as well: conquests into Irrua, for example, led to an adoption of a guerrilla warfare strategy followed by a retreat; this method was so successful that other Esan kingdoms adopted it and the British did not invade Esanland until 1901.
On March 16, 1901, the Kingdom of Uromi, headed by the old, yet intelligent Onojie Okolo, was attacked by the British. The Uromi resistance, led by Prince Okojie, was swift and employed guerrilla warfare. After a short time, British forces overtook the village Amedeokhian, where Okolo was stationed, and murdered him. This angered Prince Okojie so much that he killed the Captain of the British troops before reinforcements were brought in. The British then realized that Uromi was nigh impenetrable without native help, and contact local sympathizers such as Onokpogua, the Ezomo of Uromi. This succeeded in napping Prince Okojie out of the forest and deported to the British offices at Calabar.
This process was duplicated in most of the kingdoms that fought with Britain: guerilla warfare was excessively used by the Esans, resulting in prolonged battle time in spite of inferior weapons, and reinforcements from Benin City for the British. Even when villages were conquered, internal resistance was fierce: continued geurilla warfare in Uromi forced the British to release Prince Okojie. However, excessive cruelty on Britain’s part razed many villages and displaced many people. Finally, in 1906, Esanland submitted to British rule, and the thirty-four kingdoms became the Ishan Division.