Gabriel Bethlen (de Iktár) (Hungarian: Bethlen Gábor, Romanian: Gabriel Bethlen, German: Gabriel Bethlen von Iktár; 1580 – 15 November 1629) was a Protestant uncrowned King of Hungary (1620–21), Prince of Transylvania (1613–29) and Duke of Opole (1622–25) who led an insurrection against the House of Habsburg in Royal Hungary.