Term used by the British Empire for territories which in theory were not sovereign British territory - colonies. In theory the peoples (or their rulers) had voluntarily asked the British to undertake the government, by treaty. The practical effect was that lands of this type were not open to settlement by British farmers so that the land remained in the hands of the natives. Uganda was a protectorate, whereas Kenya was colony and protectorate: the colony being open to settlement.

The term was also used by the Nazis for Slav areas conquered during the second world war, such as Slovakia. This showed that Hitler was imitating the British Empire in his conquest of eastern Europe.

Perhaps the people who started the war in Iraq intended to make Iraq a protectorate.