Earl Alexander of Tunis is a title in the Peerage of the United Kingdom. It was created on 14 March 1952 for the prominent military commander Field Marshal Harold Alexander, 1st Viscount Alexander of Tunis. He had already been created Viscount Alexander of Tunis, of Errigal in the County of Donegal, on 1 March 1946, and was made Baron Rideau, of Ottawa and of Castle Derg in the County of Tyrone, at the same time he was given the earldom. These titles are also in the Peerage of the United Kingdom. Alexander was the third son of James Alexander, 4th Earl of Caledon.