After Nsamankow
The Asante victory at Nsamankow in January 1824, in which the British governor Sir Charles MacCarthy was killed, did not end the war on the Gold Coast. It hardened it. Over the following two years the coastal states, the British establishments and the Danish administration at Christiansborg drew together against a common opponent, while Asante under Asantehene Osei Yaw Akoto continued to press its claims over the southern territories.
By 1826 the Asante army had moved onto the open plains behind Accra. This was terrain quite unlike the forest in which Asante armies usually fought, and it favoured an opponent with artillery and cavalry-free open fields of fire. The engagement that followed, on 7 August 1826, is known as Katamanso, and also as the battle of Dodowa after the nearby town.
The Coalition
What faced the Asante was not a European army with African auxiliaries but an African coalition with European contingents attached. It included:
- Ga forces from Accra, on whose land the battle was fought;
- Fante contingents from the coastal states;
- Akyem, Akuapem and Denkyira forces, all with long-standing grievances against Kumasi;
- a small British detachment with militia from the forts;
- a Danish contingent from Christiansborg.
Estimates of the numbers on both sides in contemporary accounts vary enormously and none of them is reliable; what the sources agree on is that the armies were very large by the standards of the coast, and that the fighting lasted much of a day.
The Rockets
The single detail that dominates every account of Katamanso is the use of Congreve rockets by the allied side. These were unguided, noisy and wildly inaccurate weapons, and their military effect was probably modest. Their psychological effect on troops who had never encountered them appears to have been considerable, and the sources describe the Asante line breaking after the rockets were fired into it.
It is worth being careful here. The rocket story was repeated in European accounts because it flattered European technology, and it is likely that the outcome owed at least as much to the scale of the coalition, to the exposed ground, and to the length of the Asante supply line from Kumasi. The Asante army was defeated but not destroyed; it withdrew northwards, and the state remained intact and capable of fighting again.
The Treaty of 1831
Five years passed before the outcome was translated into a settlement. Negotiations were conducted at Cape Coast under George Maclean, then president of the merchant committee administering the British forts, and concluded in April 1831. The Asante embassy that brought them to a close was led by Akyaawa Yikwan, a royal woman whose part in the negotiation is one of the best-documented instances of a woman conducting Asante state diplomacy.
The terms required Asante to renounce claims over a number of southern states and to give sureties for its conduct — a deposit of gold held at Cape Coast and young members of the royal family sent to the coast to be educated. In return the trade roads to the coast were to remain open to Asante traders, which was the point of the whole exercise from Kumasi's perspective.
Consequences
The settlement worked, in the narrow sense that it held. The three decades that followed were the longest period of peace between Asante and the coastal establishments in the nineteenth century, and they coincide with the long, commercially minded reign of Kwaku Dua I from 1834. It was in this period that the Dutch mission under Major-General Jan Verveer travelled to Kumasi and concluded the recruitment agreement of 1837 — a treaty that would have been unthinkable during open war.
For the coastal states, Katamanso is remembered as the battle that ended Asante overlordship in the south. For Asante, it was a reverse in a long contest that continued by other means. Both are defensible readings of the same day's fighting, and the difference between them still shapes how the battle is described in Ghana today.
