War having broken out in 1812 between the United States and the United Kingdom, the islands were largely used as a base by American cruisers sent to prey on British merchant ships. This and other considerations urged by Lord Charles Somerset, then governor of Cape Colony, led the British government to authorize taking "possession" of the islands as dependencies of the Cape. The formal proclamation of annexation was made on 14 August 1816. The British wanted to ensure that the French, their repeated enemies, would not be able to use the islands as a base for a rescue operation to free Napoleon Bonaparte from his prison on Saint Helena. Attempts to colonize Inaccessible Island failed.