A Governor Looking for a War
Sir Charles MacCarthy arrived on the Gold Coast in 1822 as governor of Britain's West African settlements, taking over forts that had until then been run by a company of merchants. He inherited a coast in which Asante claimed authority over many of the Fante states, and in which the British-protected towns resented that claim. MacCarthy, an energetic administrator with a strong sense of Britain's civilising mission, decided that Asante power on the coast had to be broken rather than negotiated with.
He had reason to think it possible. He assumed, as many British officials did, that Asante armies were poorly armed levies who would not stand against disciplined musketry. He also assumed that the Fante allies he raised would fight alongside him with the same determination. Both assumptions proved wrong, and the decision to campaign in the forest during the rainy season compounded them.
The Encounter of 21 January 1824
In January 1824 MacCarthy advanced inland with a force made up of a small number of British officers and men, colonial troops, and a much larger body of allied levies. Critically, he divided his columns, and the detachment he led personally became separated from the main body. On 21 January it met the Asante army near the Bonsa river, at a place remembered as Nsamankow.
The British party was heavily outnumbered. Accounts agree that its ammunition ran out during the engagement, and that the reserve supply failed to reach it — one of the most frequently repeated details of the battle, though the reason for the failure was disputed at the time and remains so. Once the firing slackened, the Asante closed. MacCarthy was killed, along with most of his officers; only a handful of the party escaped. It was one of the most complete defeats a British force suffered in nineteenth-century West Africa.
What Followed the Battlefield
Asante practice treated the remains of a defeated enemy commander as a trophy of state, and the reports that reached the coast — that MacCarthy's skull was carried to Kumasi and kept among the regalia — were widely believed in Britain and did a great deal to shape opinion there. The details in the European accounts vary and were written by men who were not present, so they should be read with care; what is not in doubt is that the governor died in the field and that the fact of it was a profound shock in London.
Why the Defeat Mattered
Nsamankow removed at a stroke the assumption that Asante could be pushed off the coast by a modest expedition. The immediate British response was retrenchment. Within a few years the Crown withdrew from direct administration of the Gold Coast forts and handed them back to a committee of London merchants, a cheaper arrangement that lasted into the 1840s. It was under that committee that George Maclean, appointed president in 1830, pursued a policy of negotiated influence rather than confrontation — an approach that produced the treaty of 1831 and a long period of relative peace on the coast.
For Asante, the victory confirmed the strength of the army but did not settle the coastal question. Two years later, at Katamanso in 1826, a much larger allied coalition — this time including Danish and British contingents and using rocket artillery — defeated the Asante army on the Accra plains. The two battles together set the terms of the 1831 settlement: Asante gave up its claims over a number of southern states, and both sides accepted an arrangement that kept the trade roads open.
The Dutch View from Elmina
The Dutch, who held Elmina and maintained their own treaty relationship with Kumasi, watched all of this closely and stayed out of it. Their position on the coast depended on Asante goodwill, and a British campaign against Asante served them badly. Reports from the Dutch posts, preserved in the Netherlands, are one of the useful non-British sources for the period precisely because their authors had no stake in defending MacCarthy's judgement.
Memory
Nsamankow occupies a particular place in Asante historical memory as proof that the kingdom's armies could defeat a European-led force in the field. In British accounts it long served the opposite purpose, as an argument for greater force later applied. Both readings are shaped by what came afterwards, and modern historians have tended to emphasise the ordinary military reasons for the outcome — divided columns, an exhausted supply line and a badly chosen season — over any grander explanation.
