Colonial Office

The Colonial Office was a government department of the Kingdom of Great Britain and later of the United Kingdom, first created to deal with the colonial affairs of British North America but required also to oversee the increasing number of colonies of the British Empire. Despite its name, the Colonial Office was never responsible for all Britain's Imperial territories; for example, protectorates fell under the purview of the Foreign Office, and British India was ruled by the East India Company until 1858 (the Company thereafter being succeeded by the India Office as a result of the Indian Mutiny), while the role of the Colonial Office in the affairs of the Dominions changed as time passed.

The Whitehall headquarters of the Foreign, India, Home, and Colonial Offices in 1866. It was at that time occupied by all four government departments; now it serves just the Foreign, Commonwealth and Development Office.

It was headed by the Secretary of State for the Colonies, also known more informally as the Colonial Secretary.