Complex sentence: Archaeological evidence indicates that the francisca was a common weapon among the Franks, the axe became so strongly associated with the tribe that their name was derived from it, which indirectly means that the name France is ultimately also a derivative of the weapon's name.
Split into simpler sentences: Archaeological evidence indicates that the francisca was a common weapon among the Franks. The axe became so strongly associated with the tribe that their name was derived from it, which indirectly means that the name France is ultimately also a derivative of the weapon's name.