Luso is the alleged son or companion of Bacchus, the Roman god of wine and rage, to whom Roman mythology attributed the foundation of Lusitania, the present lands of Portugal and Spanish Extremadura.

With the conquest of the Iberian Peninsula by the Roman Empire, the Lusitania region was converted into a Roman province, roughly corresponding to the current area of Portugal south of the Douro River and the Spanish province of Extremadura.

Bacchus the Roman god of wine, was adapted from the Greek, Dionysus, and from Roman mythology, in this case, the god Libra