In the spring of 1917, as the war raged on, rising anti-monarchical and anti-German sentiment prompted the Prime Minister, David Lloyd George, to suggest to George V that members of the Royal Family reject their German names and titles. Though at first resistant to the idea, both the King and Queen recognized the precarious status of the monarchy in light of the recent revolution in Russia, where the Tsar (who, like the German emperor Willem II, was the King’s cousin) had been recently deposed.

As there was no established process for renaming the Royal House, the King’s private secretary, Lord Stamfordham, had to turn to Henry Farnham Burke at the College of Arms, which collected information on family lineages, for ideas. According to Jane Ridley in her recent biography of George V (which she wrote after careful consultation of the papers of Lord Stamfordham, and of Harold Nicolson, the King's official biographer), the names that were first considered include Wettin, which, rather than Coburg, was believed to be the family name of Albert, the Prince Consort; Wipper, which some in the Heralds’ College believed was Albert's true family name; and Guelph, which was the family name of the Hanoverians. All these were rejected for being too German-sounding and “unsuitably comic.”

Lord Stamfordham offered up Tudor-Stewart in attempt to connect with former English dynasties, and King George and Queen Mary did for a time favor simply Stewart. But both Lord Rosebery and H. H. Asquith, two former prime ministers who had been asked to consult on the name change, dismissed this choice given the rejection of the Stuart dynasty during and after the Glorious Revolution of 1688. According to Anne Edwards in her biography of Queen Mary, other suggestions from Prince Louis of Battenberg and the Duke of Connaught, who had also now joined the debate, included names historically associated with English monarchs: York, Lancaster, Plantagenet, England, D’Este, and Fitzroy. All of these were rejected.

In the end, Stamfordham was the one who came up with Windsor. Unlike York or Lancaster, it had never been (up to this point) the name of a royal dukedom. Windsor was the site of Windsor Castle, which had been occupied by the monarch for hundreds of years. And crucially, Windsor also had precedence as a royal style, as Edward III, who had reigned in the fourteenth century, was sometimes known as Edward of Windsor. The name Windsor was considered “as English as the earth upon which the castle stood, its smooth solid walls encircling its wards, mound, towers, and chapel” and was therefore accepted.

At a council on July 17, 1917, the King proclaimed that he and his heirs would henceforth be known as members of the House of Windsor. He and the extended Royal Family also relinquished their German titles, with many receiving British peerages in exchange.