Imperial Senate

The Imperial Senate is the representative assembly of the imperial elites of all stripes, from those who achieved their status through the noble birth to those who amassed enough wealth to have a notable influence over the imperial economy. It also includes the elites of the numerous vassal states of the Empire, for whom the Senate is the best way of sharing their opinions with the Grand Emperors.
The fall of the Second Empire has robbed it of majority of its power and importance, to the point where senatorial seats (despite carrying an immense ammount of prestige) has started to be seen by many as a liability. The centuries-long state of a de-facto military dictatorship of the Imperial Army changed the Senate into an assembly of the cash-cows, regularly squeezed with every emergency (and even more, with an usurpation attempt and a brief civil war that typically followed).
This changed recently, when the Senate members has managed to put their heads together and supported Lucius Aurelius Sylvanus, son of the overthrowned former Grand Emperor. The result has catapulted the Senate from power that was mostly titular and born of prestige and money to the one provided by prestige, money - and political power.
Putting a non-soldier on the throne was a breakthrough that was mental more than factual. The result, however, was the senators managing to unite despite their business and political differences. They understood that the Army was vulnerable for the first time in forever, and that they could manage to restore some of their ancient power - provided that they maintain the political cohesiveness for long enough.
But even then, the Senate is internally divided over what to do. The current princeps senatus - chosen due to his popularity among other senators - has turned out to be entertaining ideas that the oligarchs see as dangerous. The rest is divided over this matter.

Structure

There are five hundred senators, divided into three groups. The first two hundred are representatives of the client states of the Grand Empire. A handful of them is actually elected (most famously those of the Novian Republic), while the rest tends to chosen by the rulers of their countries (there are also quite a few countries where their ruler is titled senator, but used a deputy to speak for him/her in the Senate.
The second group are representatives of the imperial elites. Two hundred senators, typically chosen on the basis of their wealth (the average level of their buying power is the same as Earth's multibillionaires). With the way the imperial taxes work, those people are actually large contributors to the imperial warmachine, and as one can expect they would have had an influence on the imperial politics regardless of their status according to law.
The third group are one hundred permanent, hereditary senators. Descendants of notable Chosen Ones, former imperial dynasties, people rewarded with that for some rather outstanding achievements. This is the closest the Senate has to professional politicians (and lawmakers), as most of them receive a thorough education in that direction.

History

Second Era

While the Second Empire was an Empire, there was a functional difference between the executive and legislative power. While the emperors had a right to put forward laws, they all had to receive an acceptance from the Senate (the chief legislative power, who could also put forward their own law projects) to come into effect. That was a check on the power of the emperors, one of the many.
The Senate of the Second Era was almost as hierarchical and oligarchic as the one in modern times, although it was achieved by the voting system that heavily favourized the wealthy (the were no hereditary seats to begin with). The set amount of senators had to be of common origin, however, primarily to not rob the poor of their voice completely (as otherwise they might have looked for other forms of expression).
Almost all of the senators perished during the first minutes of the Twilight War, which quite decisively finished this part of the Senate's history.

Third Era

The Senate was reorganized fifty-three years into the Third Era, when the Grand Emperor decided that it is time to restore some form of civilian oversight over the military in light of the 'martial law' existing for so long that it became obvious that it's going to be a permanent thing. It was before the Army began to grow increasingly self-centered and the rules for the division between the civilian and military of the Second Era became forgotten.
It was created on the basis of various prior advisory councils and has quickly overtook the rather bumpy field of deals between the Grand Empire and the numerous post-Descent states that popped up throughout its territory. Soon Senate held both representatives of families whose business reached certain income treshold (meaning a lot of of tax income for the Empire, and tens thousands of workplaces) and the newly established client states.
However while initially the system more or less worked, this changed deeper into the Third Era. The regular usurpation attempts by ambitious officers (and occasionally crises caused by the Lost Lands) has led to the Grand Empire' rather liberal approach to the private ownership of goods and currency. It was rather common for the members of the Senate to end up paying significant contributions for the 'greater good of the realm'. They rarely had anything against when it was about the Lost Lands - after all, if the Empire fell, their businesses and lived would be gone with it. But the issue of financing civil wars and public projects (to buy popularity for the most recent Grand Emperor) was slightly more controversial.
The situation has changed when a puppet emperor was overthrowned by a military officer known as Gaius Marcus Ahenobarbus. The greed of the new emperor has pushed a large part of the Senate to support the son of the overthrown emperor, one Lucius Aurelius Sylvanus. To surprise of absolutely everyone, it worked. Lucius took over and disciplined the Imperial Army severely.
The problem was the fact that Lucius didn't see himself as being in debt to the Senate. However the very fact that the military's grip over the society was at least temporarily shattered meant that the Senate could now take advantage of its money without the (admitedly incorruptible on the larger scale) Army being able to simply force the issue with their superior firepower.
Today the Senate is doing its best to limit Emperor's control over the imperial finances by using bribes and influence in client states to take-over the Imperial Ministry of Internal Affairs. The battle, however invisible to most, are extremely fierce. Whether it will escalate into a regular civil war is anyone's guess.

Military

Combat Units

Mortals

Client-States Armies - The Senate has an access to the military personnel of the client-states, which is perhaps unsurprising considering the fact that 2/5 of its members are their representatives. While the client-state have no interest in open secession, they are much more interested in maintaining their internal freedoms and perhaps making some slight legal chances in their favour here and there.
They all have armies, and while the Imperial Army can easily engage most of them at once, their soldier count is grand. What's more, the regular battles against threats emerging from the Lost Lands keeps them sharp. While they are often less than zealous and fervent when they feel that they are defending the imperial oligarch's money sources, their number alone means that the shouldn't be underestimated.
Mercenaries - Money is power, and the Senate has enough of it to field entire armies of mercenaries (be it adventurers or regular mercenaries) if the needs arise. Of course, such forces aren't cheap and will probably not risk total annihilation just to fullfill their employer's goals. However other than that, they are extremely useful for a more indirect operations (making people disappear, assasinate someone, act as bodyguards etc.).
The Senate pays well and on time, which was enough for it to develop a reputation - getting hired by the senators is considered to be akin to striking a gold vein. For now, the amount of people who achieved fluctuated heavily and isn't particularly large, however this will most certainly change if the political situation in the Grand Empire will further deteriorate.

Type: Faction.
Allegiance: Grand Empire of Karadia
Imperial Council: Yes.
Organization Ranks:
N/A

Combat Strength
Client States Soldiers: Est. 20 000 000.
Mercenaries: On a strict 'need to' basis.