Star destroyers? No match!
—An Iron Glory-class captain
The Iron Glory was a huge ship, even larger than an Imperial-class star destroyer. It was extensively automated in many places in order to minimize the number of crew members. Although not especially maneuverable, it compensated this with considerable firepower. Due to the lack of a single resource provider for the Legion, armor quality varied from ship to ship.
The Iron Glory also had an extensive hangar bay capable of containing three hundred fighters, and fuel reserves and weapons storage chambers were located in this area.
The roots of the Iron Glory went to a project initiated by 8311 a short time before the Battle of Yavin. However, Palpatine ordered Imperial forces to arrest 8311, who escaped, but as a result the Steel Legion collapsed and the project was lost.
Years later, during the time of the New Republic, Ferd Swqaru became head of the Legion, and rediscovered the old project. Soon, Metal Fury-class cruisers were coming out of Legion construction yards, and soon the Iron Glory followed. Although expensive, the Iron Glory was nonetheless produced in reasonably large quantities. To save money on materials, the shipyards would recycle old wrecks and outdated ships. To save money on crews, many ships were staffed by droids, which somewhat hindered their effectiveness. Iron Glory were used mainly for Legion piracy operations and to guard its space-based interests, as well as to combat Legion rivals.
When the Yuuzhan Vong War broke out, Iron Glory were used extensively as the Legion focused on hindering the Vong. It proved fairly effective against the Vong, although it proved very vulnerable to Dread weapons.
After the Vong war, Iron Glory would be in use for some time, and would be upgraded with modern technology to stop them from being outdated. However, they were eventually replaced by new classes of ship.