The Senate is the Republic's legislative body, responsible for creating the common laws and regulations which apply to each Umbrian, regardless of which planet or system they occupy. Originally idealized as a 'citizens' assembly, the Senate's members are elected by broad bodies of constituents, for whom the senators serve as representatives in the deliberative process of governance.

The founding of the Republic ushered in the first unified government that was recognized as representing all Umbrians. The cornerstone of this new global governing body was the Constitution, a document outlining the rights and duties of Umbria's citizens and the manner and structure of planetary governance.

The Colonial Affairs Commission, or CAC, is a panel established by the Senate to oversee the development of Umbria's colonies and administer the various bodies that have been created to support those efforts. Its members are made up of senators and civilian appointments in equal parts, with a strong preference for those with the appropriate knowledge and experience needed to aid the Commission in its work.

Each habitable world in the Republic is represented by at least one Senator. Elected to a six year term of service, these men and women are responsible for speaking on behalf of their population's needs and preferences in the Republic's legislative body, the Senate. Amongst the most influential and important individuals in the Republic, the competition for these positions is cutthroat, and once elected, many will stop at nothing to maintain their power.

While political parties are expressly forbidden under the Republic's constitution, factionalism within the Senate can and does occur, taking a number of different forms. The two most common are the grouping of senators in support of a specific policy or proposal and Triumvir-centric influence groups.

The state of Umbrian shipbuilding at the onset of the war was woefully unsuitable for the large scale production of warships. The Republic's shipbuilders utilized a decentralized network of small to medium sized yards to produce commercial vessels and the frigates and destroyers which made up the bulk of the URN at the start of the conflict. Only a few specialized facilities existed to produce larger ship classes, and these were quickly overwhelmed with new demand.