Basic Information
A siege engine is a piece of equipment intended for use in siege warfare - usually in reference to the siege tactics of the middle-ages and thus meaning a device intended for reducing castles and similar fortifications.
Obviously this is quite a broad category of equipment and can be further digested into three sub-categories:
- Artillery - designed to reduce walls by bombardment.
- Sapping and breaching equipment - designed to reduce obstacles through engineering work.
- Escalade equipment - designed to allow troops to pass over obstacles without reducing them.
Design of these pieces of equipment - many of which were custom built on site - and their construction, siting, assembly and deployment are the purview of the siege engineer, who might well also be responsible for other aspects of the siege such as the construction of siege lines, earthworks and camps.
Artillery
Artillery has its own page. In context, these will tend towards the more primitive end of the spectrum and can be used by either side.
Sapping and Breaching Equipment
This includes both devices designed to actively attack obstacles and those designed to protect sappers at work. Attacking devices include the ram - generally a metal tipped wooden beam designed for attacking gates - and the screw and sow, similar devices, usually similar to a primitive drill bit, designed for attacking stone walls.
These were often protected in use by a gallery or similar device - a structure like a wheeled shed from inside which the sappers crewing the device could operate in (relative) safety. The mantlet - effectively a section of wooden wall on wheels served a similar purpose.
Defensive versions of these weapons include hoardings (additional defensive structures built onto walls to provide cover or to extend arcs of fire) and protective padding placed in front of damaged sections of wall.
Other reduction techniques included undermining of walls, the filling of moats and ditches with fascines and gabions and, late in the period, the use of explosives either in conjunction with mining or independantly.
Escalade Equipment
This divides more or less into ladders and siege towers (also called belfreys). The ladder is just a ladder, whilst the towers were somewhat more robust and, once pushed into place against the wall, gave the attacking troops a protected climb to parapet level and a bridge across which they could assault the wall.
Other, more outlandish devices occasionally appeared - such as lever arms capable of lifting small groups of men up to assault a wall - but these seem to have been freaks of an engineer's imagination.
Similar defensive devices also existed to allow the garrison to "fish" for members of the attacking force with lassoos, grappling hooks or harpoons.
Walls could also be escaladed by the building of a ramp - this doesn't seem to have been all that popular in the middle ages, but the Romans are known to have used this technique on several occasions.
(Perhaps) Inevitably these categories were often combined - siege towers in particular seem to have been common places to mount lightweight artillery pieces and/or to have served as galleries during the approach to the wall (often to support their own advance by filling ditches etc.).
Sources
Game and Story Use
- The use of siege equipment requires patience and technical skills, both of which were at a premium amongst the ranks of archetypal medieval generals. Siege warfare generally is a different skillset to field generalship and those who excelled at one were frequently (but not always) mediocre at best in the other.
- In a non-magic (or low magic) campaign, this gives a non-combat orientated PC something to do during a siege - his book-learning can be put towards engineering projects (always assuming that he's not doing logistics already). Likewise crafters may be of great use in an army composed mostly of professional soldiers bulked out with peasant levies.
- Conversely, some of these pieces of equipment are great targets for special operations - either to destroy them or (as in one case during the 1656 Siege of Malta) to occupy them and integrate them into the defences.