Prince Henry, Duke of Gloucester of King George V and Queen Mary. His widow became the longest-lived member of the British royal family in history. Prince Henry was born on 31 March 1900, at York Cottage, on the Sandringham Estate during the reign of his great-grandmother Queen Victoria. His father was the Duke of York (later King George V), the eldest surviving son of the Prince and Princess of Wales (later King Edward VII and Queen Alexandra). His mother was the Duchess of York (later Queen Mary), the only daughter of the Duke and Duchess of Teck. At the time of his birth, he was
Royal descendants of Queen Victoria and King Christian IX Victoria. Lastly, Victoria had two more granddaughters who became queens: Marie of Edinburgh, who married Ferdinand I of Romania, and Victoria Eugenie of Battenberg who married Alfonso XIII of Spain. Christian IX was therefore the grandfather of an emperor and two kings who all married granddaughters of Victoria, one of whom (Maud of Wales) was also a granddaughter of Christian IX. In total, five of his grandsons were reigning sovereigns. Victoria, meanwhile, was the grandmother of an emperor, a king-emperor, four queens consort and an empress consort. During the First World War (1914–1918), many monarchs of countries from both sides