In the immediate aftermath the European siege lines were strengthened, but the scale of the impending threat to African independence was still not generally predictable. Around 1890, relations between Europe and West Africa changed their character. Modern breach-loading rifles reached West African markets during the 1870s. The British began to recognise that economic inducements and diplomatic suasion might no longer suffice to protect their interests against European intrusion or African assertiveness. Once the French, British and Germans had acquired their new empires, they had to find methods of governing them. By 1905 most colonies could feel optimistic about the prospects for increasing the type of commercial exchanges already established between African agriculturists and the capitalist world. The northern Nigerian system of 'indirect rule' was a response to local circumstances before it became the basis of colonial dogma. The immediate impact of the conquest upon the lives of ordinary Africans varied enormously.