On July 17, 1917, King George V of the United Kingdom issued a royal decree announcing that the name of the British royal family would henceforth be known as Windsor.
1917 was a critical year for the Allied powers in World War I. That summer, it appeared as if the German forces would punch through and overrun the Allies. With anti-German feelings running rampant throughout Britain, the King grew anxious about his own position.
King George belonged to the House of Saxe-Coburg-Gotha, which came to the British throne with his father, Edward VII, whose father was Prince Albert of Saxe-Coburg-Gotha. George's wife, Queen Mary, was a princess of Teck by birth, a morganatic branch of the royal house of the German kingdom of Wurttemburg. Summing up the suspicions of many Britons, novelist H.G. Wells declared that King George reigned over "an alien and uninspiring court", to which the king retorted "I may be uninspiring, but I'm damned if I'm an alien".
It became clear that the royal family would have to discard their German ties if they were to retain the support of the British people. In a stroke of political genius, George V's advisers suggested he change the name of the royal house from Saxe-Coburg-Gotha to Windsor. Thus, on July 17 it was declared by order of the King that all male-line descendants of Queen Victoria would henceforth belong to the House of Windsor.