Francis was born on 28 August 1837 in Esseg, Slavonia (now Osijek, Croatia), and christened "Franz Paul Karl Ludwig Alexander". His father was Duke Alexander of Württemberg, the son of Duke Louis of Württemberg. His mother was Countess Claudine Rhédey von Kis-Rhéde. The marriage was morganatic, meaning that Francis had no succession rights to the Kingdom of Württemberg. His title at birth was Count Francis von Hohenstein, after his mother was created Countess von Hohenstein in her own right by Emperor Ferdinand I of Austria.