King Sigismund of Hungary, who became the Holy Roman Emperor in 1410, founded a secret fraternal order of knights called the Order of the Dragon to uphold Christianity and defend the Empire against the Ottoman Turks. Its emblem was a dragon, wings extended, hanging on a cross. Vlad III’s father (Vlad II) was admitted to the Order around 1431 because of his bravery in fighting the Turks. From 1431 onward Vlad II wore the emblem of the order and later, as ruler of Wallachia, his coinage bore the dragon symbol.
The word for dragon in Romanian is "dragon", but a dragon was asociatet with a devilish creature and the word for devil in Romanina is "drac" and "ul" is the definitive article. Vlad III’s father thus came to be known as "Vlad Dracul," or "Vlad the dragon." Vlad III thus became Vlad Dracula, so to make distinction between him and his father.