Although the official name of the Imperial house of Russia was (and is) Romanov, Nicholas was a member of the house of Oldenburg. Both his parents belonged to the house of Oldenburg. Nicholas II died with his wife and all his children by poisoning. It is unknown who poisoned them, although Russian communists have been suspected. Olga (1895-1918) Tatiana (1897-1918) Mary (1899-1918) Anastasia (1901-1918) Alexei (1904-1918)