The United Nations Navy (UNN) is the naval branch of the United Nations military. It is considered less technologically advanced than its Martian counterpart, the Martian Congressional Republic Navy, but has the largest fleet in Sol system and is considered to be overall superior.

In 16 XTE, the United Nations Navy was absorbed into the Consolidated Fleet, which, in turn, waged war against the Free Navy during the Free Navy Conflict.


Earth’s military, primarily the United Nations Navy and the United Nations Marine Corps, is arguably the most powerful combined military force in the system. Most of the UN Navy is spread throughout the solar system, overseeing and protecting Earth’s interests in the Belt and the Outers or keeping the peace as part of the Earth-Mars Coalition Navy. While not as technologically advanced as the navy of the Martian Congressional Republic, the United Nations Navy is considerably larger, consisting of capital ships such as Dreadnoughts and Battleships, as well as smaller vessels like Cruisers, Destroyers, Frigates, Corvettes, and more. Nevertheless, projections have shown that the technological superiority of Mars would give them the edge against Earth’s numbers in any major conflict between the two planets. The United Nations Marine Corps serves aboard UN Navy vessels and guards Earth outposts in the Belt and beyond. Marines wear vacuum-rated and radiation shielded powered armor, enabling them to engage in combat operations virtually anywhere in the system. The UNMC can place over 100 million troops on the battlefield, far outnumbering the ground forces of any other nation including Mars, and the fact that UN marines are born, raised, live, and train in the one full gravity of Earth gives them a considerable advantage against opponents accustomed to the lower gravities of Mars or the Belt. The current leader of the Outer Planets Alliance, Fred Johnson, was formerly a colonel in the United Nations Marine Corps, where he gained infamy throughout the system as the “Butcher of Anderson Station.”[1]

Structure Edit

The exact structure and ranking system of the United Nations Navy remain largely unknown.

However, according to on-screen information, the UNN is headed by the Fleet Commander (a 4 or 5 star Admiral), who is the senior-most member of the Navy and has a seat in the United Nations Security Council.

The Navy itself is divided into several permanent fleets, each commanded by an Admiral. Each fleet has its assigned area of responsibility. For example, Third Fleet's area of responsibility is Jupiter and its moons; hence, it's known as the "Jupiter Fleet". However, in times of war, this division becomes rather fluid. For the purpose of executing various missions, the Navy creates temporary units of lesser size, which may consist of ships from different fleets - these units are called Task Forces. The example is Thomas Princes Task Force - a unit of UNN which was created for the sole purpose of traveling to the Ring, and later into the Slow Zone itself.

UNN rank structure is somehow unclear due to noticeable differences between that and 21st century Navy rank insignias but, it generally resembles the structure and insignias of western nations' navies.

The following UNN ranks were shown on screen:


Designation Appears Notes
Bush shipyards TV and Books Multiple Epstein drives stolen from here for Protogen's secret Amun-Ra-class stealth ships.

Fleets Edit

The United Nations Navy is divided into two main fleets. Several smaller fleets also operate as part of the main fleets were required:

Designation Commanding Admirals Appearances Notes
UNN Home fleet Admiral Pycior
Admiral Souther
TV and Books Operated in the inner solar system near Earth and Mars.
UNN Jupiter fleet Admiral Souther
Admiral Nguyễn
TV and Books Operates in the Jupiter A.O. and the Belt.
UNN 3rd fleet Admiral Souther TV Operated as part of the Jupiter fleet during UN-MCR War
UNN 5th fleet Unknown Commander TV Enroute to the Jupiter A.O. and reinforce the 3rd fleet.
UNN 8th fleet Unknown Commander TV Converging with the 3rd and 5th fleets.

Ships Edit

Designation Class Ship type Appearances Notes
UNN Agatha King Truman-class Dreadnought Caliban's War (Books) UNN Fleet Command Flagship commanded by Admiral Nguyễn and taken to Jovian moon Io.
Season 3 (TV) UNN Jupiter Fleet Flagship commanded by Admiral Souther and taken over by Admiral Nguyễn and sent to Jovian moon Io.
UNN Okimbo Caliban's War (Books) UN Jupiter Fleet Flagship commanded by Admiral Souther over Jovian moon Io
UNN Thomas Prince Xerxes-class (Books) Truman-class (TV) Battleship (Books) / Dreadnought (TV) Season 3 (TV)
Abaddon's Gate (Books)
Carried various religious clergy and artists into the Ring.
UNN Nathan Hale Leonidas-class Battleship
Season 2 (TV) Sent by the UN to arrest Fred Johnson on Tycho Station. Raced the MCRN Scirocco to Phoebe until the MCRN Scirocco destroyed the station.
UNN Zhang Fei (Books)
Zheng Fei (TV)[3]
Unknown class Destroyer (TV)
James Holden had been posted aboard this vessel when he was discharged
UNN Yasijuro Unknown class Destroyer Season 3 (TV) Crippled by an MCR cruiser in the Vesta Blockade. Current status unknown.
UNN Seung Un Unknown class Destroyer

(Books) / Fleet Support Ship(TV) || Season 3 (TV)
Abaddon's Gate (Books) || Sabotaged outside The Ring in plot to discredit James Holden

UNN Wu Tsao Unknown class Frigate Caliban's War (Books) Part of fleet Admiral Nguyễn had sent to Ganymede but which Avasarala disbanded
UNN Ravi Phantom-class Corvette Leviathan Wakes "The Butcher of Anderson Station" (Books)
UNN Feodorovna Unknown class Gunship Caliban's War (Books) One of the ships Avasarala couldn't divert away from Ganymede
UNN Jimenez Unknown class Patrol Torpedo Boat

[4] || Season 3 (TV) || Destroyed by the UNN Agatha King for betraying the orders of Fleet Admiral Nguyễn.

UNN Heisserer Unknown class Patrol Torpedo Boat

[4] || Season 3 (TV) || Refused to acknowledge Admiral Nguyễn and moved away from the Third Fleet before Jimenez's destruction.

UNN Orinoco Unknown class Unknown Season 1 (TV) Attempted to intercept the Donnager but would not arrive until two days later when the engagement would have ended.
UNN Mikhaylov Unknown class Unknown Caliban's War (Books) One of the ship's Admiral Nguyen tried to sneak over to Ganymede.
UNN Dagmar Unknown class Marine assault craft[5] "The Butcher of Anderson Station" (Books)
UNN Darius Unknown class Unknown Caliban's War (Books) Present at Io Campaign
UNN Greenville Unknown class Unknown Caliban's War (Books)
UNN Tanaka Unknown class Unknown Caliban's War (Books)
UNN Dyson Unknown class Unknown Caliban's War (Books)
UNN Kennedy Unknown class Unknown Caliban's War (Books)
UNN Triton Unknown class Unknown Caliban's War (Books)
UNN Battle Angel Unknown class Unknown Season 3 (TV) Present at Io Campaign
UNN Halpenny Unknown class Unknown Season 3 (TV)
UNN Hodson Unknown class Unknown Season 3 (TV)
UNN S.A. Corey Unknown class Unknown Season 3 (TV)
UNN The Victor Unknown class Unknown Season 3 (TV)
UNN Campsi Unknown class Unknown Season 3 (TV)
UNN Mograph Unknown class Unknown Season 3 (TV)
UNN Countee Cullen Unknown class Unknown Season 3 (TV) Carried all civilians off Thomas Prince before the dreadnought entered the slow zone.
UNN Edward Carr Unknown class Unknown Babylon's Ashes (Books) Was damaged and in need of extensive repairs during Free Navy Conflict.
UNN August Marchant Unknown class Unknown Babylon's Ashes (Books) Escorted the cargo ship Minsky from Ceres to Earth[6]
UNN Bethany Thomas Unknown class Unknown Babylon's Ashes (Books)
UNN Bernadette Koe Medical support ship Unknown Caliban's War (Books) One of the ships Avasarala couldn't divert away from Ganymede.
UNN Charles Lyell Military research vessel Unknown Leviathan Wakes (Books) Commandeered by the UNN to investigate Eros along with escort.
UNS Arboghast(TV)
UNN Arboghast(Books)
Civilian research vessel Unknown Season 2 (TV) Commandeered by the UNN to investigate the Eros crash site on Venus.
Military science vessel Converted former third-generation Destroyer[7] Caliban's War (Books) 572 souls onboard killed when disasembled by the Protomolecule
UNN Aristophanes Unknown class Transport Caliban's War (Books) One of the ships Avasarala couldn't divert away from Ganymede.
UNN Cerisier Unknown Fleet maintenance ship Abaddon's Gate (Books)

History Edit

Eros Incident Edit

When the Donnager is destroyed by what is believed to be OPA ships, and Mars declares war on the Belt, the the UN stays neutral. Later when Holden released information on the ships that destroyed the Donnager were actually made on Earth, UNN ships fired on Martian Congressional Republic Navy ships in Mars' orbit and destroyed the Deimos deep radar station. After securing Martian space, the UNN begin laying siege to Mars, forcing, the MCRN then orders nearly all their ships in the system to return to Mars and declares war on Earth. The Belt claims it a victory, and the siege lasts for months. However, all combat remains in orbit and doesn't spread onto Martian soil.

The Charles Lyell, a science vessel, escorted by the Ravi, was doing a non-Belt asteroid mapping when it was diverted to Eros to collect samples of the Protomolecule. It was in a confrontation with the Rocinante until they finally worked together to stop the asteroid.

Ganymede IncidentEdit

In the eighteen months since the Eros incident the MCR and UN have been in a bitter cold war.

The Ganymede incident was an event where a human-protomolecule hybrid attacked Martian and UN Marines on Ganymede, killing everyone except Gunnery Sergeant Roberta Draper. The initial attack was misinterpreted by both the MCR and the UN as an attack from the other side, which lead to a battle above and on Ganymede that claimed nearly three thousand military and civilian lives, as well as over five billion MCR dollars of infrastructure damage.

Post Free Navy ConflictEdit

At the end of the conflict only three of the UNN's Battleships are still operational, two of which are deployed to the Slow Zone to guard the Laconia system gate.

Laconian DominanceEdit

After the defeat to the Laconian Imperial Navy the UNN was still permitted to operate as part of the Earth-Mars Coalition Navy in policing operations in the Sol system.

Prior to the Eros IncidentEdit

Sometime after the Donnager came under attack, also there was jamming in the area. UNN Fleet Commander, Admiral Souther dispacted a warship to find out what is going on.

Eros IncidentEdit

Ganymede IncidentEdit

Slow Zone IncidentEdit

Free Navy ConflictEdit

Ship-classes in serviceEdit

Class Ship type Appearances Photo Notes
Xerxes-class Battleship Books The largest UNN warship. Comparable in size to the MCRN's Donnager-class.
Truman-class Dreadnought TV and Books Truman NorthFront UNN command ship. At least 4 in service during UN-MCR War.
Leonidas-class Battleship TV Conceptartleonidasclass2
Unknown Class Destroyer TV/comic Expanseoriginscomicno1zhengfei James Holden served onboard a ship of this class the Zhang Fei.
Munroe-class Light Destroyer Books Admiral Nguyễn sent six destroyers of this class to destroy the Rocinante[8][9]
Phantom-class Corvette Books Outdated but still in service during UN-MCR Cold War
UNN unidentified ship type Unknown TV S03E07unnfleetunnamedshipclass18m35s Several engaged in combat with PDCs during the Ganymede Incident. Two ships of this class later escorted the UNN Thomas Prince into the Slow Zone.
Marine assault craft[10] Breaching ship Books Capable of carrying up to 200 Marines and breaching stations directly. Requires escort ships for defense.
Fleet support ships Non-combat support TV Unnseungun1

Gallery Edit

See alsoEdit


  1. The Expanse Roleplaying Game, chapter 8 - Earth
  2. Spacedock Leonidas-class video:
  3. The TV adaptation referred to James Holden's ship with a similar but distinct name. It is unknown whether that was intentional or a goof.
  4. 4.0 4.1 the tone used when the remark was made suggests it may actually have been just a form of denigration and not an actual PT boat
  5. The Expanse Novella: "The Butcher of Anderson Station"
  6. The Expanse Novel: Babylon's Ashes, Chapter 25, Fred
  7. The Expanse Novel: Caliban's War, Chapter 23, Avasarala
  8. The Expanse Novel: Caliban's War, Chapter 39
  9. The Expanse: Caliban's War, Chapter 42
  10. The Expanse Novella: "The Butcher of Anderson Station"
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