What's interesting is that the real surname of the British royal family is German:

"The British royal family changed their last name from Saxe-Coburg-Gotha to Windsor in 1917. The reason? World War One broke out in 1914 and anit-German sentiment was at its height in 1917. In protest, King George V renounced all the German titles belonging to him and his family and adopted the name of his castle, Windsor.

Here's a look at the proclamation:

from the date of this Our Royal Proclamation Our House and Family shall be styled and known as the House and Family of Windsor, and that all the descendants in the male line of Our said Grandmother Queen Victoria who are subjects of these Realms, other than female descendants who may marry or may have married, shall bear the said Name of Windsor.

The Royal family name of Windsor was confirmed by Queen Elizabeth II after her accession in 1952. However, in 1960, The Queen and The Duke of Edinburgh decided they wanted their direct descendants to be distinguished from the rest of the Royal family (without changing the name of the Royal House), as Windsor is the surname used by all the male and unmarried female descendants of King George V.

Soon thereafter, it was declared that The Queen's descendants (other than those with the style of Royal Highness and the title of Prince/Princess, or female descendants who marry) would carry the name of Mountbatten-Windsor. (In 1947, when Prince Philip of Greece took the Oath of Allegiance, he became naturalized, and assumed the name of Philip Mountbatten as a Lieutenant in the Royal Navy.) "

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".