Foresail

[4] A two-masted merchant vessel with a sizable foresail rigged on a slightly inclined foremast is depicted in an Etruscan tomb painting from 475 to 450 BC.

[7] Artemon, along with mainsail and topsail, developed into the standard rig of seagoing vessels in imperial times, complemented by a mizzen on the largest freighters.

[8] Throughout antiquity, both foresail and mizzen remained secondary in terms of canvas size, but still large enough to require full running rigging.

[8] By the onset of the Early Middle Ages, rigging had undergone a fundamental transformation in Mediterranean navigation: the lateen which had long evolved on smaller Greco-Roman craft replaced the square rig, the chief sail type of the ancients, which practically disappeared from the record until the 14th century (while it remained dominant in northern Europe).

To balance out the sail plan the next obvious step was to add a mast fore of the main-mast, which first appears on a Catalan vessel from 1409.

The foresail (in pink) of a full rigged ship.
Model of ancient Greek trireme with raked foresail, called artemon