|Council of Judges, Spyders|
The Noble Houses
The Noble Houses are semi-autonomous governments which control their own slices of human space, though they must obey the dictates of the Keiser. The name is actually a misnomer; while many Houses are run by hereditary landed nobility, others have a more corporate structure, while a few houses (may) even experiment with slightly more democratic methods of governance (complete with corruption and seniority-based systems to help those in power stay in power).
The Laansraad Aes
The Houses themselves appoint representatives to the Laansraad Aes, or Supreme Council Of Nobles, which is the legislative body which governs the Noble Houses. The Laansraad drafts legislation for the Republic, as well as serving as a forum for the Noble Houses to settle disputes without turning to military action, or so the theory goes. In practice, the Landsraad merely acts out the animosities of its members, sometimes to the point of fistfights breaking out on the floor.
The Senatus Custodies
Laws proposed by the Laansraad are approved (or not) by the Senatus Custodies. Half of the twelve Custodies are appointed by the Laansraad themselves, while the other half are appointed by the Grand Prophet. In addition to approving laws, the Custodies also control the appointment of the Magestratum, the Magistrates (Judges) of the Republic.
Each House has their own military, composed of soldiers levied from the various worlds under the House’s rule and of Star Knights, from an Order tied to the House itself, hired Mercenary Orders, and/or Knight-Guardians loaned from the Church.
The Keiser Aes
The Keiser is the Supreme Emperor of the Republic. Every 300 years, or upon the death of the previous Keiser, the Landsraad selects one it's own to wear the crown of light.
The Armie Republicae
The Armie Republicae is less an army than a coordinating command structure (think NATO) between the separate forces of the Church (The Militum) and the Laansarmie; which is controlled by the Emperor and the Nobles of the Laansraad.
Every Keiser has the authority to levy troops from the Noble Houses, and to command them to military action as part of the Laansarmie. The largest of the 3 major military organizations of the Republic. Which currently comprises some 55% of all it's military forces. The Emperor, however, does not have full control of the Laansarmie. It's use must be authorized by the Laansraad prior to any action. Which puts certain political constraints on their use.
The Eccleasiae Militum
The Eccleasiae Militum, or simply 'The Militim', are the military forces of the Church of Terra Ascendant. They are raised from church members, gifts of men and equipment from the Nobles, and are augmented by the Church's own cloning facilities.
Upon his death, the family of the old Keiser is expected to give over a significant portion of his personal House forces (50 percent, usually) to the Church in return for his granting of sainthood. As the Emperor is usually is able to greatly expand his own forces by using the taxes he levies on the other Nobles, this gift has the effect of re-balancing his House's influence within the Laansraad so that it cannot challenge the other Nobles militarily and upset the political balance.
By tradition, approximately 85% of the Church's military forces are placed at the disposal of the Emperor for military actions approved by the Senate. However, these forces can always be withdrawn if the Church feels that the Keiser is not sufficiently ‘demonstrating his faith’.
Thanks to the troops tithed by various Kaisers over the years, and their own levies, the Militum has grown to such a size that it can match any three House armies combined. In addition to the Church’s Knight-Guardians, the Church Militant fields a large number of both fully and technologically modified humans in military roles.
The current Supreme Emperor of the Republic is Geiran Huang Lehr of House Lehr. Who first took the Throne 256 years ago. The Lehrshand, therefore, are his personal house forces. Levied from the star systems that are directly controlled by his own family. Paid for with the taxes he collects from the other Noble Houses.
As their absolute master, the Emperor is free to deploy the Lehrshand as he pleases. As such, they are often the first military forces to respond to new threats. As well as the primary enforcers of the Emperor's will against disobedient Noble Houses or rogue elements of the Church. For which proper authorization for use of the Laansarmie or the Church Militant would be... impractical politically.
The Church Of Terra Ascendant
In terms of wielded power, the Noble Houses are primarily opposed by the Church of Terra Ascendant. While the people believe that the Church opposes the power of the Noble Houses on their behalf, the truth is that the Church’s primary loyalty is to its own ambitions for mankind's future.
At the head of the Church is the Pontifex Prophetae (literally: 'Prophet Of Prophets'), the most powerful man in the Republic. The Grand Prophet (as he is also known) possesses absolute veto power: if he so desires he can block any law or stop almost any appointment, though these powers are rarely exercised. In addition, the Grand Prophet is the supreme commander of the Church’s army, the Church Militant, and appoints some very important governmental figures.
The Holy Councils
Below the Grand Prophet are two Councils: the Fidelis Coteu (council of the Fatihful) and the Prophitae Concilo (Council of Prophets). The Fidelis Coteu are the highest members of the Fidelis (the non-Prophet administration of the Church), and the Prophitae Concilo is composed of some of the highest-ranking Prophets. The two councils together appoint the Grand Prophet.
The Ordos Gemina
One of the most important powers possessed by the Church is its monopoly on human cloning; by law, only the Ordos Gemina may clone humans. The Ordos’ labs primarily produce Prophets and Knight-Guardians for the Church, although the Emperor has limited access to the labs for his own armies. Depending on how well he has demonstrated his faith recently.