Thrasimund I or Transamund I was the Count of Capua and then Duke of Spoleto (663 – 703 AD),[1] a faithful follower of Grimoald I of Benevento.
Thrasimund assisted Grimoald in usurping the kingship of the Lombards. In return, Grimoald gave him his daughter in marriage and granted him the duchy of Spoleto after the death of Atto. Thrasimund co-ruled with his brother Wachilapus[2] and was succeeded by his son Faroald II after a reign of forty years.