Ármin Vámbéry (1832-1913), a Hungarian scholar and traveller, is thought by some to have been the model for Van Helsing. Vámbéry, who spoke multiple languages, made a detailed study of the Ottoman Empire, and compiled a German-Turkish dictionary. He travelled for some years around Central Asia disguised as a dervish. On his return to Hungary, he was appointed Professor of Oriental Languages at the University of Budapest.
In 2005 it was revealed that Vámbéry had been employed as a spy by the British Government, working against Russia in the Great Game.
Vámbéry met Bram Stoker in London in 1890, although the extent to which he influenced the author is much disputed by Dracula scholars.