UNSC Secret Annexe

Background
By the late 2480s, rebellion and insurrection began forcing the UNSC to expand it's fleets and forces to meet the challenges posed by millions of colonists who were restless with the current system of government. Massive rearmament and recruiting ballooned the size of the UNSC fleet to a much larger and more effective force.

Construction
In early 2489, construction began on the UNSC Secret Annexe, with an estimated delivery date of July 7th, 2491. It was one of the newest ships being constructed, the newly revamped and remade FFG class. The Annexe was one of 100 new frigates constructed over Mars, and was an engineering marvel at the time.

Service
In July of 2491, the Annexe left the shipyards and accelerated out-system on a vector for more contested space. In it's belly was the 29th Marine Division, and a small compliment of 700 ODSTs. The Annexe saw first combat in 2492, during the nuking of the Far Isle colony. The Annexe was part of a force of 25 ships that launched an attack on rebels on the planet, and during a six month campaign, the ship and it's crew clashed in open combat with enemies on the ground and in vacuum. During the campaign, the Annexe often would descend into the atmosphere and deliver troops directly to the front. However, after six months of extended fighting without much accomplished, and faced with an imminent nuclear strike originating from the surface, the UNSC bombarded the entire colony with nuclear weapons, destroying it completely.

However, this event did not destroy rebellion in the colonies, but rather increase it. Dozens of new rebel factions began popping up, such as the URF, and the Annexe was pressed into heavy service. In 2494, the Eridanus rebellion, otherwise known as the Insurrection, began, and the Annexe took part in operation TREBUCHET. However, during a low altitude landing mission on Tribute, a surprise rebel attack badly damaged the ship, and it was forced to withdraw. The Annexe served with distinction for several years, until in 2525, a new enemy attacked.

The Covenant, a conglomerate of alien races, attacked the UNSC with brutal force. After the loss of the outer colony Harvest, the entire UNSC fleet was placed on high alert, and Admiral Cole marshaled a fleet to retake the planet. However, the Annexe was not chosen for this fleet. Rather, it was assigned to one of the many small patrol groups assigned to protect the outer colonies. For ten years, the Annexe, along with two other ships, the Toronto and the Cherokee. Both of these ships were destroyers, and the Annexe was vital as it had a much needed troop battalion.

However, despite the best efforts of the UNSC fleet, the last of the outer colonies fell in 2535. As the UNSC fleet was forced back into the inner colonies, the Annexe joined a fleet under the command of the then Vice Admiral Carl Patterson. This fleet, compromised of three destroyers, six frigates (including the Annexe), 1 Carrier, and 12 Corvettes. This force was one of the largest in it's sector of the inner colonies. However, due to engagements with the covenant, the fleet sustained heavy losses, and by 2549, it had been widdled down to one destroyer, three frigates, one carrier, and 2 corvettes.

In 2549, the fleet was deployed to Paris IV, and deployed it's marine forces to the surface. Ground combat was extremely fearsome, and only actions of heroism, such as Avery J. Johnson's hijacking of a crate of plasma grenades, allowed the UNSC to hold out long enough to evacuate civilians. The space battle was actually at first a success, with the UNSC fleet holding out with the loss of three ships and destroying Covenant resistance. Hundreds of transport craft were overloaded with civilians, and almost 1 billion people escaped.

However, the tide of the battle soon turned. A force of 17 Covenant ships entered the system, and the fleet was decimated. The Annexe was gutted from stem to stern, and was only saved when the Lincoln, a destroyer, and the only remaining operational ship attached to it via hard points and transported it back to safety. After two years in the shipyards, the Annexe was finally repaired and the ship returned to front line duty. The ship was modernized with a more powerful engine system, and was placed in the Earth home fleet. The ship was badly damaged during the Second Battle of Earth, and crashed into Luna.

Reconstruction
For the second time in it's lifetime, the Annexe was repaired, and this time, it's weapons and armor was heavily updated. Energy shielding was installed, a more resilient hull was created, pulse lasers were placed in lie of 50mm point defense guns, and Model 9 Grindell/Galileian Directed Energy Pusle Weapons were planted across the hull. The Annexe was given a much more advanced slipspace drive and a much faster sub-light engine system. The Annexe was ready to fight. For several years, the Annexe served against rebels, and then later, the Covenant Remnant and Covenant Rebels. During the years, the new captain, Captain Ruth Longshot, showed his skill and led the ship to several victories and allowed it to become a very helpful ship to the fleet.

However, in the late 2590s, the Annexe was retired; newer ships were being put into service, and the Annexe was obsolete. However, instead of being scrapped, the ship was downgraded back to it's original Great War state, and the ship was placed in the museum of humanity as an outdoor exhibit.