Siegecraft originated in Ancient Greece. This type of siege originated from the moment in which the stage of the mere siege was surpassed by an exceptional development of military techniques, which were hardly taken any further during the Middle Ages, until the invention of firearms. The importance of siege techniques was due to the increase in the strategic role of the city to the detriment of the territory in the overall defense of the polis.
Origins
Apart from the Mycenae tablet, in which slingers, archers and stone throwers are seen fighting a battle under the walls of a city, Homer's description of the chariot assault launched by the Trojans against the fortified camp of the Achaeans, and the anecdote of the Trojan Horse, there is nothing, except the fortifications discovered by archaeologists, that informs us about the evolution of Greek poliorcetics before the end of the Archaic Period.
Since the Neolithic, defensive concerns have presided over the organization of the urban plan. More than through the construction of fortified enclosures of very limited size and extent, one can observe the adaptation of civil architecture itself for military purposes: the streets are narrow and winding, while the walls of the houses are sometimes reinforced to serve as defensive wall, especially on the edges of the agglomerations. This protection system, despite its rudimentary appearance, is of great efficiency and allows to make the best use of the natural features of the terrain, with the least effort. In the 4th century B.C. it was still recommended by Plato, in Laws, who was concerned not to separate topographically the device of collective defense from the ordinary framework of private life, in order to increase the combativeness of the citizens.
The structural autonomy and architectural power of walled enclosures tended, however, to be reinforced in the course of the 1st millennium B.C., given the progress of construction techniques, the enrichment of communities and the concentration of social resources in the hands of palace aristocracies (perhaps also influenced by the Hittites, who by that time had already forged a reputation as experts in fortification).
Between the middle of the 14th century B.C. and the end of the 13th century B.C. the Mycenaean acropolis, then royal residences, was surrounded by imposing defensive walls of Cyclopean blocks, more or less well hewn and laid without mortar. Their width varied between 4 and 17 m, and their height between 4 and 9 m. Their layout was generally determined by the orography, but sometimes it was also divided into short rectilinear sections separated by small slits, as in Gla, a place located on an island in the Copais lake of Boeotia. The openings were scarce: four gates at Gla, a gate and a postern at Mycenae, Tiryns and Athens, generally provided with an access ramp parallel to the defensive wall and also flanked by massive projections forming a forecourt, as at Tiryns, or by towers, as at Mycenae, Athens and Gla.
The gates were the only weak points of the fortified perimeter; hence the exceptional precautions taken to force the assailant to present himself before them in an unfavorable position, on his left side, which was not protected by the shield and exposed to the weapons of the defenders. It was rather by besieging them that one could hope to seize these fortresses, in which the population of the territory probably took refuge; for this reason, the builders often took the precaution of fitting out subway galleries leading to fountains located at the foot of the defensive walls.
It does not seem that before the 5th century B.C. there was any modification in the art of fortifications and siege procedures. What is important in urban enclosures, whose number increased considerably from the archaic period onwards, was their static value, the passive aspect of their power; formed by a structure of sun-dried bricks, generally founded on a base of dressed stones, with few openings and equipped with some square flanking towers (especially near the gates), they were clearly not designed to withstand a full-fledged assault.
Historians' accounts show that besieges were, until the Peloponnesian War, the most widespread and effective method of siege. Once a countervaluation wall of unfired bricks or dry-laid stones had been built, sometimes supplemented on the outside by a circumvallation wall, the besiegers had no choice but to stand guard, draw on their reserves and be patient. In this way they recognized their inability to force their way into the city; an inability that revealed, above all, their reluctance to take such a risk, since for them, the main issue in the conflict was control of the territory.