The Ekumeku — the word means roughly 'the whirlwind' or 'the secret' in western Igbo — was a confederation of guerrilla resistance movements among the Anioma (western Igbo) towns of Asaba, Onitsha-Olona, Ibusa, Akumazi, Idumuje, Ukwunzu, Issele-Uku, Akwukwu and adjoining communities, which fought a thirty-year insurgency against the Royal Niger Company (1879–1900) and then the Southern Nigeria Protectorate (1900–1914) along the western bank of the Niger.
The sequence is roughly: an 1883 confrontation with the Niger Company over the Company's monopoly on river trade; major risings in 1898, 1902, 1904, 1909 and 1909–11; and a final, sustained campaign suppressed only by the 1909–1911 Ekumeku War in which the colonial force burned villages, deported the *obi* of Ogwashi-Uku and seven other senior title-holders, and finally accepted, in 1914, an uneasy peace under indirect rule.
The Ekumeku is distinctive for three reasons.
First, its organisational form. It was not a kingdom and had no permanent army. It was a sworn brotherhood drawn from the age-grade and title societies of the Anioma towns, coordinated by *Ekumeku* lodges that imposed an oath of secrecy on members. British intelligence officers complained throughout the period that they could never identify a 'leader' to negotiate with or arrest: the movement reconstituted itself after each defeat from a different combination of towns.
Second, its tactical sophistication. It combined dawn raids on Company stores and Native Court buildings with assassinations of colonial collaborators (chief warrant officers, court messengers, native-court clerks), with rapid dispersal into the forest. It was, in modern terms, the first sustained guerrilla insurgency in southern Nigeria — and one of the longest-running.
Third, its political reading. The Ekumeku is often described — in nationalist historiography from Nnamdi Azikiwe forward — as the 'first nationalist movement' in southern Nigeria. The descriptor is anachronistic but not arbitrary: by the 1909 risings, oaths recorded by colonial intelligence explicitly invoked solidarity with the Aro, with the still-resisting Tiv and with the Sokoto Caliphate, against a common British enemy.
The colonial response — burning towns, deporting *obis* to Calabar and Lokoja, fining whole communities collectively — destroyed the formal Anioma political structure and stripped the title societies of independent income. By the time the Southern Protectorate amalgamated with the North in 1914, the western Igbo had paid a higher proportional cost in lives and property than any other group in the colonial conquest of southern Nigeria — and had earned the right to be remembered as the longest-resisting.