Midi-chlorian/Legends

"Without the midi-chlorians, life could not exist, and we would have no knowledge of the Force. They continually speak to us, telling us the will of the Force. When you learn to quiet your mind, you'll hear them speaking to you."

- Qui-Gon Jinn to Anakin Skywalker

Midi-chlorians were microscopic life forms that existed inside the cells of all living things. While they were not the Force itself, they formed a link to it, acting as a sort of sensory organ through which it could be perceived. Midi-chlorians enabled the perception of the Force just as having eyes allowed people to see light or having ears allowed them to interpret vibrations as sound. If an individual had enough midi-chlorians in their body they could use them to communicate with the Force. In essence, midi-chlorians were the connection between a being’s mind and the Force, enabling certain sentients to intentionally manipulate it, or allow themselves to be manipulated by it.

Historical significance
A high midi-chlorian count was usually an indication of Force-sensitivity, meaning that the creature had the potential to become a Jedi. The Jedi Order was always on the lookout for Force-sensitives, who would be brought to the Jedi Temple and inducted into the ways of the Force. To further this goal, the Jedi learned how to quiet their minds and focus, so they would be able to sense the midi-chlorians that lay inside of other creatures. Once a being was suspected of having a high midi-chlorian count, a simple blood test could be administered to determine a definite amount.

During the reign of the Galactic Empire, midi-chlorian tests were performed to root out Force-sensitives and Jedi in hiding. Such individuals were rarely heard from again. In response, an underground trade of drugs and blood treatments sprang up that could supposedly fool a test or lower one's count; however, they were largely ineffective. The Emperor placed a ban on all information regarding Jedi or the Force from public data banks and medical libraries. When Kornell Divini found that Nova Stihl had a high count of midi-chlorians, he did not know much about them and could not research information about them. Divini inquired the MedNet on the forbidden subject and Darth Vader was alerted to the warning flag that he tripped.

Midi-chlorian research
"The reading's off the chart—over twenty thousand. Even Master Yoda doesn't have a midi-chlorian count that high!"

- Obi-Wan Kenobi to Qui-Gon Jinn

The Rakata were thought to have experimented with medically transferring midi-chlorians into other beings in an attempt to transfer Force-sensitivity. They supplanted the genes responsible for midi-chlorians from Force-sensitives into their own genetic code to try and help their race 'remember' forgotten Force abilities. It is not known whether these experiments had any success, as the Rakata believed it would still take many generations for the experiment to be complete.

Millennia later, scientists had been known to increase the midi-chlorian count of normal individuals on Vjun by artificial means. However, this led to many extremely Force-sensitive people who did not know how to control their power, and in turn, many of these Force-enhanced beings went insane. The Malreaux family was an example: Whirry Malreaux was a housewife who read the future in broken things and went insane after the death of her father. However, her son Whie Malreaux was taken away by the Jedi to begin Jedi training, and was spared from losing his mind. Whie also had premonitions and dreams of the future, similar to those of his mother and Anakin Skywalker.

When Supreme Chancellor Palpatine told Anakin Skywalker of the so-called "Tragedy of Darth Plagueis the Wise", he spoke of the legendary Sith Lord acquiring the power to "influence the midi-chlorians to create life". It is not clear whether or not Palpatine was lying on this occasion.

Latent Force-sensitivity could also be artificially activated or magnified; some members of the reborn Palpatine's Dark Side Elite benefited from this process. Years later, the Dark Jedi Desann managed to artificially infuse the Force to regular individuals (not known if they were latent or even not sensitive at all) by using special Artusian crystals. Whether his method had anything to do with midi-chlorians remains a mystery, but it is thought that either the crystals caused the midi-chlorians to multiply or somehow 'reinforced' the ones that already existed, producing a totally artificial Force-sensitivity.

Another method Desann used to artificially reinforce Force sensitivity in beings was to channel (dark) Force-energies into their bodies. Desann referred to these people as the Reborn. The name suggests that the infused Force energies could be the souls of dead Force-users. It may be possible that this method also artificially increased the midi-chlorian count in the "host-body".

Normal Jedi Midi-Chlorian Counts
According to Obi-Wan Kenobi, Anakin Skywalker surpassed Master Yoda in midi-chlorians, more than twenty thousand per cell. Master Yoda was considered the strongest in the Jedi Order. Exact numbers could be also placed on non-Jedi Nova Stihl at over 5,000 midi-chlorians per cell, more than twice of a normal human.

Origins
The concept of midi-chlorians was first mentioned by George Lucas as early as 1977, when he included them in his first guidelines for Expanded Universe authors. However, the idea was introduced to the general public some twenty-two years later in 1999's Star Wars Episode I: The Phantom Menace, in which the organisms were revealed to be an indicator of an individual's sensitivity to the Force. It is possible that while midi-chlorians provide a way to communicate with the Force, they are also a measure of Force ability as a whole. This idea is supported by the fact that Anakin Skywalker, Luke Skywalker, and Yoda&mdash;the three Jedi with the highest known midi-chlorian counts in the Jedi Order&mdash;seem to be the most prone to visions received through the Force; or at least more so than others of similar Force ability (such as Mace Windu).

Pre-Phantom Menace Expanded Universe materials hinted at an individual's biological connection to the Force. In Jedi Search, Lando Calrissian carries out a search for potential Jedi for Luke's new academy by using a device that can supposedly detect affinity to the Force. In The Thrawn Trilogy, two organisms are mentioned, the ysalimiri and the vornskrs, that have "evolved" the ability to use or block the Force in a predator-prey relationship. While the vornskrs have evolved the ability in order to hunt, the ysalimiri have responded with the ability to generate "Force bubbles" in which the Force cannot be used. Novels following release of the sequels in The New Jedi Order series would reinforce this basis in biology by describing beings whose makeup made them inherently resistant to the Force: the Yuuzhan Vong and the voxyn.

Despite how it might first appear, the existence of inanimate, yet Force-enhancing objects such as rocks and crystals does not seem to contradict the midi-chlorian explanation. The various crystals and other Force-enhancing objects would work like a magnifying glass, multiplying the power the Force-user puts in.

In real science, midi-chlorians appear to be based on mitochondria, which were once separate organisms that inhabited living cells and have since become part of them. Mitochondria are the power plants of cells, suggesting that perhaps midi-chlorians create the energy of life and thus the Force. Unlike midi-chlorians, which in the Skywalker family are passed on by both father and mother, mitochondrial DNA is only transmitted on the maternal side. In 2006&mdash;perhaps as a tribute to this similarity&mdash;a newly discovered species of bacteria was named Midichloria mitochondrii after the midi-chlorians.

On April 1, 2006, several entries relating to George Lucas' Willow universe were added to the StarWars.com Databank as an April Fools' Day joke. The update page states that midi-chlorians may have originated on the planet Andowyne.

Controversy
Some see midi-chlorians as adding hard science to the alleged "mysteriousness" of the Force and dislike what they see as a new concept. However, while it appears that the idea had never been published, the concept of a biological basis for the Force was hardly a fresh idea. Luke and Leia's inheritance of Force powers as children of Darth Vader already suggested such a power was hereditary and thus based in one's genes. Additionally, several novels printed before the prequels were released had similarly carried the suggestion that sensitivity to the Force was a biological phenomenon.

Steve Perry, who dealt with them in his Death Star novel, called them "less than inspired."

Appearances

 * Star Wars Knights of the Old Republic
 * Tag & Bink: Revenge of the Clone Menace
 * Darth Maul: Shadow Hunter
 * Star Wars Episode I: The Phantom Menace
 * Star Wars Episode I: The Phantom Menace comic
 * Episode I: Qui-Gon Jinn
 * Star Wars Republic: Darkness
 * Rogue Planet
 * Rather Darkness Visible
 * Star Wars Republic 64: Bloodlines
 * Republic Commando: True Colors
 * MedStar II: Jedi Healer
 * Yoda: Dark Rendezvous
 * Star Wars Episode III: Revenge of the Sith
 * Star Wars Episode III: Revenge of the Sith comic
 * The Rise and Fall of Darth Vader
 * The Last of the Jedi: A Tangled Web
 * Death Star
 * The Return of Tag & Bink: Special Edition
 * Star Wars Tales 10 intro
 * Revelation
 * Revelation