These weapons were of the so-called "antennae", "biglobular", or "carp tongue" swords used by both Celts and Celtiberians, very practical for initiative attacks, since being short and light they could launch an attack very quickly, especially lunges, for which they had a long point. They could also be used by hacking, which many times did not help much, since the enemy could wear a chain mail; But, in case they had to take a cut, they were double-edged. The original Hispanic swords were measured for each person and made of high quality iron, which was treated in a special way resulting in very good weapons. The gladio has been considered the best sword that has ever existed from a practical and strategic point of view and the one that caused the most deaths in ancient times.
The gladius was designed for quick lunge attacks. This was very practical, since the Roman legionary who carried the sword took cover behind a scutum; once the enemy had uselessly landed his blow on the Roman's shield or armor, or was about to do so, the Roman would launch a quick thrust with his agile gladius, thus stabbing and killing the opponent. The gladius was replaced by the spatha, copied from the Germanic barbarians.
Recent archaeological discoveries of very old versions of the gladius suggest, however, that the Hispanic origin of this weapon is actually related to an Iberian variant of the "La Tène" type sword, named after those found at La Tène and elsewhere. archaeological sites of the culture of the same Gallic name. In what is now France, this sword was lengthening and becoming more cut, even being manufactured without a point, while in Hispania a smaller size and more suitable for the double function of the cut and lunge was preserved. In this Spanish version the original Roman gladius would be inspired, which, over time, would become shorter and shorter: more than stabbing.
Originally, the Romans used a type of characteristics very similar to the Iberian original, with a double edge and a long point, capable with a vigorous thrust of penetrating chain mail. But it was evolving to simpler forms, until it reached the «Pompeii» model, named after the swords found in that city. This model has a completely straight blade, and the tip is shorter. This is said to be so because, with the barbarian enemies of Rome rarely wearing armor, a shorter point was sufficient and there was less risk of "getting caught" in the ribs of the victim when impaled. But the most likely reason is simply that they were simpler and therefore faster and cheaper to manufacture.