Head rod of a marionette. Fil d’archal is a French term, still used today by some puppeteers to describe a key string in the manipulation of a puppet.

European marionettes are traditionally operated by means of a rod or wire attached to the head of the puppet. This may vary from a slender brass wire to a stout steel rod such as we find with the Sicilian pupi today. The rod (wire) may be attached to a staple planted in the top of the head of the puppet or may be fixed into the head, and sometimes hooked onto a staple or wire at the neck to create a joint with the torso. The head rod was usually accompanied by strings to the hands, and sometimes the legs, but in some cases a second rod controlled the right arm to allow for strong movements with a weapon (Antwerp poesje, Sicilian pupi).

In England by the mid-19th century the head rod was being replaced by a pair of strings attached to the sides of the head. Where possible these strings were a strong linen thread that had been waxed, but in more modern times this has been replaced by nylon and other synthetic materials.

The transition from the head rod to the head strings (which in some cases remained light-weight brass wire) had a major impact on the operation of the puppet and strong movements were replaced by more delicate ones dictated by gravity.

(See Rod Marionette.)