Before 1917, members of the British Royal Family had no surname, but only the name of the house or dynasty to which they belonged.That all changed with WW1.
Victoria was the last monarch of the House of Hanover .
She was a Kent ....Her Royal Highness Princess Victoria of Kent .Her father was The Prince Edward Augustus, Duke of Kent and Strathearn and her mother Princess Victoria of Saxe-Coburg-Saalfeld. A rush job to provide an heir .
...she never took the name Saxe -Coburg although some of her children did I think ..Edward certainly ..