Historically, members of Royal families had no need for 'surnames', as 
Kings and princes were known by the names of the countries over which they and 
their families ruled. Kings and queens therefore signed themselves by their 
first names only, a tradition in the United Kingdom which has continued to the 
present day (see style and title). 
   Members of the British Royal family had no surname before 1917, but only 
the 
name of the dynasty to which they belonged.   The names of dynasties tended to 
change when the line of succession was taken by a rival faction within the 
family (e.g. Henry IV and the Lancastrians, Edward IV and the Yorkists, Henry 
VII and the Tudors), or when succession passed to a different family branch 
through females (e.g. Henry II and the Angevins, James I and the Stuarts, 
George I and the Hanoverians).
   Just as children can take their surnames from their father, so sovereigns 
normally take the name of their `House` from their father. For this reason, 
Queen Victoria`s eldest son Edward VII belonged to the House of Saxe-Coburg-
Gotha (the family name of his father Prince Albert). Edward VII`s son George V 
became the second king of that dynasty when he succeeded to the throne in 1910.