In my campaign, skyships were created by The Celestial Kingdom which is a magocracy. They had a monopoly on the construction and enchantment of skyships. Eventually the High Elves of the Forest Kingdom started growing their own liftwood which led to open warfare between the two kingdoms. While the High Elves of the Forest Kingdom took heavy casualties and a portion of the forest was burnt to the ground, the High Elves were able to call in allies (Sky Elves and their Aerii (bird-men) allies, Grey Elves with their Atlantean allies, and even some human allies). More about the Celestial -Elven War can be found
here.
As for my rules on skyships, here's what I have:
Skyships can only fly within the atmosphere (they do not have their own air supply), but there are rumours that specially crafted Skyships have been to the moons and back. The Celestial Kingdom neither deny or confirm these rumours. Skyships are made from a rare wood called liftwood that can only be found within the borders of the Celestial Kingdom. The natural properties of this wood make them naturally lighter than air. The liftwood trees grow to gargantuan heights and once a limb is broken/cut off the tree, it will float upwards unless restrained.
Skyships consist of vessels of all sort of sizes and shapes depending on the vessel's purpose (from small caravels to grandiose galleons). The majority of these vessels appear as standard sailing ships, but an inspection inside would reveal the skyhelm that is need to power these ships. Skyhelms are ornate throne-like seats that are bolted to the ship. Once a special magical ritual is performed on an inert skyhelm, it becomes enchanted and active, ready for a magic-user to power the ship for flight. Once a ship has bonded with its 'Master' (re: the Magic-User who pilots the ship) it will not work with any other Magic-Users unless the previous master is dead or has released the ship from its service (once released, the MU may not re-bond with the ship).
When used on the sea, these ships use the appropriate water movement rates for a vessel of the same class (i.e. a Skyship galleon behaves like a normal galleon when travelling on water). When travelling in the air, use the following formula to determine its airspeed:
(INT + Level) x 10 = air speed in mph
For example, an 8th Level magic-user with an intelligence of 16 could power a skyship to move at an airpseed of 230 mph.
The statistics for Skyships break down as follows (I've been using the format used in Spelljammer):
Tonnage:
Crew:
Maneuverability Class (MC):
Armour Rating (AR):
Hull Points (HP):
Saving Throw:
Keel Length (KL):
Beam Length (BL):
Standard Armament (SA):
Ram:
Landing:
Land –
Water –
Cheers,
Tim