During my work on my next character I found that an entire historical background partially about Kumogakure and about a faction of my invention was needed for my character's history, so far this is what I have written.
I have already discussed some of the details with Sonic, I have since expanded upon them but I will be glad for any constructive criticism and ideas.
Feel free to use this thread for your own needs.
Following the assassination of Killer B by the hands of unknown attackers the Eight tails was sealed inside a containment urn as Kumogakure searched for host candidates. After a number of failed and destructive attempts to reseal the council of Elders successfully lobbied for the creation of a facility designed to address the issue far away from the village thus saving in form further demonic rampages.
What began as an attempt to understand the demon's Chakra and find a means to contain and exploit it failed to deliver any significant results. Sadonaga, a prominent village Elder was able to secure control over the facility and soon replaced its staff with members of his own "special unit".
The special unit was a number of interest groups taken under the wing of Sadonaga and his clan. Unofficial in its nature the special unit became increasingly powerful after the days of the fourth Shinobi Great War and was largely responsible for the rise of Sadonaga's power and consequently its own.
Upon establishing itself in absolute control over the eight tales facility the special unit reached its zenith of power and insured Sadonaga's will and vision where carried out.
Sadonaga decreed that the eight tales was by nature a bloodthirsty creature and that changing this nature was only possible by the power of its host. Killer Bee was a rare example of one able to truly control a tailed beast however he was a rarity and therefor to Sadonaga's thinking the only way to create a suitable host was to match the host to the nature of the beast while guaranteeing the host would be completely obedient to its masters and with as much consciousness as a Kunai.
Dozens of village members had already died as result of the sealing effort thereby rendering any further acquisition of other villagers impossible unless the facility could guarantee their safety. On the surface the facility claimed and seemed to be working towards this goal however in truth it had since turned to acquiring further host candidates from other means.
Mass raids by the facility struck the land of the waves completely destroying many small isolated fishing villages, the young of these villages where taken to the facility while the other inhabitants where all killed in order to destroy all evidence of what had transpired.
These young where trained in a way similar to what had been practiced in the land of water during the "bloody mist" however Sadonaga designed ever more efficient ways of training which increasingly distanced themselves from the policy of Kumogakure. Despite some investigations the facility kept its true operation away from the attention of the village and its Kage however some suspicious assassinations of prominent enemies of the facility plan led to rumors and suspicions which slowly grew as the special unit expanded.
After eleven years of operation and eight years of the ultimate shinobi plan the facility remained with twenty host candidates. These candidates were ordered to slay each other until only one remained, after three days of fighting only the one who would later be known as Daichi remained and was thus made the host of the eight tails.
An undercover spy sent by the Raikage (is that ok?) was able to escape the facility and deliver the news to the Raikage, by the time a force arrived the entire facility had been systematically destroyed by the maddened host who had allowed the eight tales to control his body in order to bring vengeance against the facility. Elder Sadonaga was never found however enough information of his continued existence and operation was found to justify declaring him a rouge Shinobi.
The host was overpowered by the force and taken back to the village where the seal was enforced to prevent another such occurrence. Despite some calls to terminate his existence the host was judged stable enough to continue carrying the eight tales as long as the seal remained in force and the host did not experience madness such as what had transpired in the facility. In order to guarantee the hosts stability his memories where removed and fake ones implanted instead of these to insure the host's loyalty to the village however some memories remained.
Update
I think a better choice of events would be to have my character massacre much of the facility until it is faced with Sadonaga who is able to overcome the eight tales and render my character immobile. The force from the village arrives in time to stop Sadonaga from taking the character with him however Sadonaga is able to escape.
