Answer
Maria Alexandrovna of Russia was the only Romanov to marry into the British royal family. She was the daughter of Alexander II of Russia and his wife, Maria Alexandrovna of Hesse and by Rhine. Maria married Alfred, Duke of Edinburgh, the second son of Queen Victoria and Prince Albert of Saxe-Coburg and Gotha, in 1874. The couple had eight children, including the future King George V of the United Kingdom.