There were some Shard, however, that were still more persecuted than the rest,
for they were a menace in yet another sense.
For not only were they aliens, and not only were they droids, they were Jedi.

What is an Iron Knight?
An Iron Knight is the combination of a force-sensitive sentient being known as a Shard, that has been installed or implanted into a droid body. Originally the first Iron Knights were implanted in three distinct type of droid bodies. During the year 50 BBY, a group of Jedi moved to intervene on the behalf of the Dominion's forces during the Arkanian civil war. Among the Jedi that came to help in that bloody battle was a Sunsei Jedi Master by the name of Aquinos, who had been a pioneer in the field of introducing the Force into non-organics. The Iron Knights proved invaluable in the battle, and with their combined forces with the Jedi and their police bash squads, helped to minimize casualties in what would have been a sure-fire massacre. Aquinos had successfully taken force-sensitive Shards from their home planet of Orax and introduced them into droid bodies. This way they could interact with the outside world, and from the teachings of Aquinos learned how to control the Force and use it akin to that of the Jedi Order.
Despite their efforts however, Aquinos was ex-communicated from the Jedi Order and banished. The Jedi at that time viewed this to be a heretical act to teach the Force to beings that essentially did not have organic life. Shards are living beings, but their anatomy is very alien, as they do not contain living tissue, organs, or even brains as other organics beings do. However, despite these glaring differences, they are able to think, feel, and understand - and when paired with a droid body, they could control it like it was the mind, heart, and soul of the machine. Many Iron Knights took on the name of the lightsaber crystal that inhabited their saber, such as the original leader of their kind; Illum.

What happened to the Iron Knights?
After Aquinos was banished from the Order, he went into seclusion becoming a Altisian Jedi; a frowned upon sect that taught other ideals than the traditionally minded ones from the council. Despite the banishment, he continued to train his Iron Knights, and because of their seclusion, were not picked up in the sweeping genocide that was Order 66 by hiding out on the planet Dweem in the Outer Rim. For seventy years, the Iron Knights stayed out of commission and out of the line of sight. Thanks to the Shard's vast lifespan, and the droids ability to maintain for many decades, they were able to survive and stay safe while the Empire rose to power and then subsequently was destroyed.
Once the New Order of Jedi had resurfaced some seventy years after the great purge, a group of students followed clues given by Callista Ming in order to find these brave warriors. Once they were found, the Iron Knights were keen to rejoin the Jedi. This new group embraced them instead of showing the prejudice from the previous incarnation of the Jedi. While it was unfortunate that their creator and founder; Aquinos, would die in the Yuuzhang Vong war, the Iron Knights championed the cause with the Jedi to drive back those vile creatures during such a Galactic war.
Several wars were fought by their kind, especially against the Red Knights of LIfe, a sect of the Vong that were bent on the hatred of technology. They were even credited with saving the Kligson moon, a salvaged heap of mechanical parts that was home to a myriad of droids - once targeted by the Red Knights.

How to become an Iron Knight
The requirements for being an Iron Knight are rather simple, but there are certain rules that must be followed in order to qualify.
  1. Your character must be of the Shard species.
  2. Your character must be installed in a droid.
  3. Your character must be of the Republic Faction to be considered part of the Iron Knights.
Iron Knights will be trained like any other student of the Force, and can progress from Padawan, to Knight, to Master. They will still be called an Iron Knight throughout this process, as the term Iron Knight does not denote their rank in the board's eyes. The Iron Knights follow the Jedi Code, and they are subject to the council like any other Jedi.
Iron Knights do not have to exclusively be put into the three droids mentioned in the canon history, but can be put into any other kind of droid that can interact with the world. It is helpful to have an articulate droid that is able to move, manipulate the environment with appendages, and speak.