The most well-documented event of Samo's career was his victory over the Frankish royal army under Dagobert I in 631 or 632. Provoked to action by a "violent quarrel in the Pannonian kingdom of the Avars or Huns" during his ninth year (631–32), Dagobert led three armies against the Wends, the largest being his own Austrasian army. The Franks were routed near Wogastisburg (Latin "castrum Vogastisburg"), an unidentified location meaning "fortress/castle of Vogast." The majority of the besieging armies were slaughtered, while the rest of the troops fled, leaving weapons and other equipment lying on the ground. In the aftermath of the Wendish victory, Samo invaded Frankish Thuringia several times and undertook looting raids there. The Sorbian prince Dervan abandoned the Franks and "placed himself and his people under Samo's realm".