At once the land is both united and divided. There is a single Emperor that oversees all subjects, but there also exist divisions between the classes within the Empire. Nowhere is this more apparent then in the ranks of the military.

Samurai

At the top, just below the Emperor, are the nobles. These are the warriors clad as Samurai; skilled warriors of tradition and honor. From birth members of the nobility are bound to service for the Emperor. These members of the nobility consider themselves superior to the lower classes, and avoid mangling with the “savage” ninjas. They bare heavy armor and use only swords for weapons. Since a Samurai’s worth is measured in his skill in the art of war, it is essential that a child of the aristocracy learn to properly fight, and more importantly learn to wield the katana and wakizashi.
The katana a Samurai wields is one of sacred ancestry. It is tradition for the blade of a Samurai to be passed down through the lineage of the family. While the weapon may endure many generations, it never dulls or tarnishes. Samurai blades are blessed by the spirit of the gods, and are impervious to damages just so long as they remain in the use of their respected families; this assures that if a Samurai is defeated his opponent cannot steal his blade.
The strength of the Samurai is comparable to the age of the blade he wields, and the strongest families are the eldest in ancestry. Samurai do not release chakra, like ninjas do, but instead absorb the life force through their swords. When an opponent falls at the hand of a Samurai katana or wakizashi their chakra, the basic life force within them, is infused into the weapon, making it stronger. Samurai control this chakra by unifying their own chakra with their blades. Furthermore, the tradition of seppuku when faces with shame or defeat serves the purpose of preserving the strength of the family. The tanto that is also passed down through the family line contains the souls of all passed Samurai of that lineage.
Samurai compose the generals of the Military. They are the ‘Arm of the Emperor’.

Ninja

Below the Samurai are the ninjas. These are the warriors of discipline and deception. Ninja techniques come from the manifestation of chakra into powerful skills and abilities known as jutsus. There are three deviations of jutsu; Taijutsu that draws from the martial arts, Genjutsu that are illusionary mind techniques, and Ninjutsu that categorizes all other jutsu skills. While Ninja are considered lower then Samurai, they have a stronger connection with nature since they do not inherit their abilities in a physical object. Furthermore, Ninjas have a wider variety of abilities open to them.
Within the Empire there exist several “Nations”, whose borders matter only to the Ninja villages. Ninja techniques are relative to their respective nation, and each region of the land produces uniquely skilled Ninja. The existence of the nations represents the power struggle between the Ninja villages, which are hidden from all other villages. Only the Emperor knows the location of all the Ninja Villages.
Within each Hidden Village there is a Ninja academy used for training the next generation of Ninja. These academies serve as a breeding ground for Genin, which then become Chuunin and then Jounin. Ninja are used not for leading large armies like the Samurai, but instead for specialty missions requiring both stealth and skill. The level of importance ranges from civilian to imperial, and the ranking system that Ninjas have develop effects the level of mission importance they can take on. Since the abilities of a Ninja represent the teaching of their village, there are specialized Hunter Ninja that are responsible for killing and disposing of rogue Ninja that possess secrets within their jutsu techniques.
Ninjas are the ‘Spirit of the Emperor’.

Sumoes

Even beneath the Ninjas are the Sumo. Sumo warriors do not pertain only to the hefty wrestlers, but also include any master of the various martial arts. What separates the Sumo abilities from those of Taijutsu is that Sumo techniques do not use chakra to enhance strength or speed. Sumoes are the basic fighters, ranked above typical soldiers because of their strength and endurance.
Sumoes are the ‘Strength of the Emperor’.

The other classes are the soldiers that serve in the Military, and the civilians that live their lives underneath the rule and protection of the Emperor. Civilians and soldiers are able to become Sumo and Ninja with training, but the rank of Samurai is exclusive to an individual’s family heritage.

Battousai

The Battousai are the most honored of warriors. They are the elite patrons of the Empire, selected to serve outside of the lower ranks. The Battousai keep order throughout the land, dealing in secret with threats unknown to the common folk. The ranks of the Battousai are composed of members of all lower ranks. It is through this organization that Ninja and Sumo alike can surpass the Samurai in grander, for the members of the Battousai are hand selected by the Emperor to serve their nation. Only when a Battousai is slain may another raise to their ranks, and no one save the Emperor knows exactly how many there are. To the civilians and lower soldiers the Battousai are only myths, but to the Samurai, Ninja, and Sumoes they are a goal.
The Battousai are the “Blades of the Emperor”.