Attila gathered his vassals -- Gepids , Ostrogoths , Burgundians , Heruls , Rugians , Scirians , Alans , Thuringians , among others -- and began his march west . Attila gathered his vassals -- Gepids , Ostrogoths , Rugians , Scirians , Heruls , Thuringians , Alans , Burgundians , among others -- and began his march west .