Survival as an empire was another reason for Britain's interest in Africa after 1869. The British economy has always depended heavily on trade, and having colonies was the way to expand trade. Before the 1870's, the British had very little competition in gathering colonies--Germany and Italy were not unified, the French were busy fighting with the Prussians, and the revolutions of 1848 created internal instability in other European countries. They didn't have any interest in external affairs. However, by 1871, Germany and Italy were unified. France had just lost Alsace-Lorraine to the Germans after the Franco-Prussian war, and were being encouraged by the Germans to look for colonies in Africa to regain national pride (and also to try to help them to not be so upset over losing Alsace-Lorraine). In order to encourage the French, Bismarck, who had never wanted colonies before, began some imperialism in Africa. France quickly followed. The English were suddenly faced with competition. They felt if they did not take over land first, the Germans or the French would and thus take away their markets. They also believed that if Britain didn't expand, she would lose the colonies she already had to Germany and France. Because of this, the British mentality was that the Germans and French forced them to expand to save the empire. An economic depression in Europe in the 1870's and the 1880's didn't help matters. The British believed that markets were scarce because foreigners (especially Germans) were taking them all, and if other countries cut Britain off in foreign trade, she would no longer be economically first, no longer an empire. So, in 1883 the British divided up the Niger with France, and began taking colonies in 1884 out of fear after Germany claimed Togo and Cameroon as protectorates. They tried to take control of the Sudan while supporting the Italians against Menelik in 1896. The British also had an excuse for their imperialism; many of the colonies were supported by trade and not by taxpayers. In short, land was cheap.
After 1890, the reasons behind British imperialism in Africa were the same, with a new one added. The British had no allies. Colonies would provide them with allies around the world. They believed that they were already in an economic war with Germany, and a real war would not be far behind. Some referred to imperialism as gearing up for war. During 1897 France was still angry about losing the Suez Canal. Russia looked interested in India, and was encouraging France to be angry against England. France and Britain also began the "Battle of the Flags," a dispute about towns along the Niger River that almost led to war. In 1898 the British took Khartoum. In 1901 they annexed from Ashanti to the Gold Coast, and in 1903 they added to Nigeria. The British war hawks turned out to be right; World War I began in 1914.
From 1869 until nearly the start of
World War I, the British practiced imperialism in Africa out of
fear of losing their empire. They took South Africa and Egypt to
keep India from being stolen, and they annexed other parts of
Africa (such as areas around the Niger) to compete economically
with France and Germany, and to keep the land they already had from
being taken by France and Germany. They also annexed land in order
to have allies in case a war should start. The British claimed they
didn't want to practice imperialism; that Germany and France forced
them to do it to keep their empire. Maybe so, but fear of losing
the British economic status and the British empire to Germany and
France, not Germany and France forcing imperialism down the English
people's throat, seems to be the better answer to why the British
practiced imperialism in Africa from 1869 to 1913.