The 1653 Instrument of Government (republican constitution) stated: Oliver Cromwell, Captain-General of the forces of England, Scotland and Ireland, shall be, and is hereby declared to be, Lord Protector of the Commonwealth of England, Scotland and Ireland, and the dominions thereto belonging, for his life.The replacement constitution of 1657, the Humble Petition and Advice,[1] gave "His Highness the Lord Protector" the power to nominate his successor.

George exercised the powers of the monarchy, just as Lords Protector had, but the title's republican associations had rendered it distasteful.

In the novel The Last Man by Mary Shelley, Britain becomes a republic with its elected head of state styled as Lord Protector.

In 1987 television series The New Statesman finale episode "The Irresistible Rise of Alan B'Stard", after B'Stard's New Patriotic Party wins a landslide majority in a special general election called over British membership of the European Economic Community but with himself not having contested a seat, he briefly considered adopting the title of Lord Protector before being permitted to serve as an extra-parliamentary Prime Minister.

In the 2008 film adaptation of C. S. Lewis' Prince Caspian, the antagonist Miraz begins as Lord Protector of Narnia before being proclaimed King (a change from the novel).