The British Royal Family, also referred to as the House of Windsor, is a branch of the Germanic House of Saxe-Coburg and Gotha. As a result of British hostilities with Germany in the First World War, the family anglicised their surname to Windsor in a Royal proclamation of 17th July, 1917.
Queen Elizabeth II is the most senior member of the British Royal Family. He is the reigning monarch of all the Commonwealth countries. However, the overall head of the House of Windsor is actually Prince Richard, the Duke of Gloucester, who is the most senior descendant of the male line of King George V, the monarch who founded the House of Windsor when he decided to change his surname to Windsor. Andreas, the Prince of Saxe-Coburg and Gotha heads the entire ‘House’.
Queen Victoria married into the house of Saxe-Coburg and Gotha through her marriage to Prince Albert. Queen Victoria actually wanted her future son to rule in the name of the ancient House of Wettin, to which the Saxe-Coburg Gothas were a minor branch, as she felt it would strengthen his position, tying him into the Saxon heritage that Germany and England share, but the idea never gained wide acceptance and with the First World War, the name was erased forever from the British Royal Family.
The final decision to change the Royal name was taken after the heavy German aircraft, the Gotha G.IV directly bombed London. The name could not longer be ignored, especially when the abdication of Tsar Nicholas II of Russia (first cousin to King George) coincided with this event, making it obvious that the Europeans Royal houses could indeed be toppled. Also at this time, Prince Louis of Battenberg chose to anglicise his name to Mountbatten. This Prince Louis is the grandfather to the Queen’s husband, Prince Philip, Duke of Edinburgh. Today, the only royals to carry the Windsor name are descendants of George V.
Prince Philip is himself of Greek and Danish descent, a member of the House of Schleswig-Holstein-Sonderburg-Glücksburg. Upon his marriage to the then Princess Elizabeth, it would have been customary for her to take his name. However, fearing a repeat of the historical problems linked to war and territorial wrangles, it was decided that the Windsor surname should be retained. Future monarchs may change this, but the hair to the throne, Prince Charles, has shown no wish to do so.
George V had five sons, and of their descendants, two have died (including Princess Margaret, sister to the Queen). Seven others are Catholic and therefore not eligible to take the throne. The remaining thirty-nine people make up the official line of succession to the British and Commonwealth throne.
The current Queen Elizabeth II may never have been a monarch at all. George V’s eldest son, Edward, succeeded to the throne upon his father’s death. However, his reign lasted less than a year. He caused a constitutional crisis by proposing marriage to an American divorcee, Wallis Simpson. This marriage was deeply unpopular with Prime Minister, Stanley Baldwin and he threatened a general election. The King forcing such a situation would have ruined the historical position of a politically neutral monarch. So, rather than create this situation, he chose to abdicate in December 1936.
His younger brother, Albert, came to the throne, adopting the regnal name of younger George VI, and it is from him that the current Queen Elizabeth descends, as his eldest daughter.