40px-Terminal.png This article, Mazovia, was written by LoyalHaloFan. Please do not edit this fiction without the writer's permission.
40px-Super_optimal.png The author of this article, Mazovia, urges anyone who reads it to provide feedback on the quality of the article. Thank you!


Outer Colonies


Eta Leporis system

Distance from Core

49 light-years

Rotation period

30.782 hours (30 hours, 47 minutes)

Orbital period

282.34 Earth days




8,949 kilometers


Composition: N2, O2, Ar, CO2, trace

  • Average Surface Temperature:
    • -43.51°C to 55.81°C (-46.32°F to 132.46°F)

1.049 G

Official language
  • English (de facto)
  • Nov Polćsi (since 2436)
  • Polish
  • Czech
  • Slovak
  • 44,321,997 (2525)
  • 27,671,983 (Great Panic)
  • <7 million (2540)
Major cities
  • Sněžka (Capital and largest city)
  • Toruń
  • Pilecki
Major exports
  • Iridium
  • Titanium
  • Food products

"History always repeats itself. From the Hydra System massacres to the abandoning of Mazovia, why does Earth care so little for their citizens?"
―Excerpt from The Colonial, 2556

Mazovia, also known as Eta Leporis II (η Leporis II), was an outer colony terrestrial world, mostly known for its titanium mines and agriculture industry. The second planet of four in the Eta Leporis system, Mazovia was situated in favorable conditions for human colonization during the Domus Diaspora. With very few mountains, hills and deserts, Mazovia provided vast kilometers of arable land, allowing the colony to develop a large agricultural industry and become one of humanity's many breadbasket worlds. Mazovia a member of the trade union Agrobelt, a network of agriculture-dominant Outer Colonies responsible for feeding the majority of the human population.

Mazovia was settled in 2397 during the first phase of the second wave of colonization that established the Outer Colonies. The colony was one of the last worlds funded by Earth government organizations, as the 25th Century began, more and more Outer Colonies would be formed out of corporate contracts or people trying to escape the grasp of Earth. Funded by the Visegrád Group, with assistance by the European Union, the colony ships UES Jaroslav Heyrovský and UES Witold Pilecki departed from the influence of Earth in February 2397 and would travel the next six months in slipspace before reaching and settling the world of Mazovia in August 2397.

Mazovia is often considered the most developed Outer Colony world, with some believing that it should be given Inner Colony status after a report of its gross colonial product (GCP) in 2489 showing it way ahead of other Outer Colonies. While the colony has historically been seen as more prosperous and well-off compared to other Outer Colonies, the history of Mazovia is a complicated and bloody one.

Recent History

Human discovery

Mazovia was discovered in 2027 during a five year planet-hunting project spearheaded by the European Space Agency with cooperation with the National Aeronautics and Space Administration that began in 2026. Using the Spitzer Space Telescope, NASA used the telescope to observe the Eta Leporis system using transit method. The telescope discovered three planetary bodies orbiting the star, two being gas giants and the third being a terrestrial world. Following a number of other discoveries, the Spitzer Space Telescope was officially retired by NASA, serving for twenty-four years, far beyond its intended mission length.

Mazovia's transit in 2026 taken by the Spitzer Space Telescope.

A year later in 2027, the ESA would observe the Eta Leporis system again, using its PLATO space observatory to scan the system. Fortunately, using the transit method once again, PLATO confirmed the existence of the previously discovered planetary bodies, but also discovered that the system's second planet contained two orbiting natural satellites. PLATO also discovered an anomaly within the star's dust disk, with a mass similar to Mercury's. Using a combination of several techniques such as radial velocity, Doppler beaming, and transit-timing, along with cooperation with the La Silla Observatory to confirm its findings. Together, PLATO and La Silla discovered the existence of a fourth planet situated deep inside the star's dust disk. More exciting, further observations by both observatories, with assistance from the HARPS spectrograph, new data indicated that the second planet featured Earth-like characteristics. Located less than fifty light-years away, this planet would be one of the closest Earth-like exoplanets to be discovered.



Human-Covenant War

Military Presence & Security

Mazovian Militia

The Mazovian Militia was formed in 2501 by the colonial government as a proactive measure to the escalating Insurrection conflict and uncertainty of it spreading to the colony. As the the conflict engulfed much of the Outer Colonies, Mazovia had been lucky enough to avoid a major skirmish and had only been concerned with minor uprisings and the occasional act of terrorism over the next twenty years.

Mazovian Militia auto-rifleman.

As the colony enjoyed a relatively peaceful period of history in a time of mass civil instability, the Militia that had been specifically created to put down major rebellions fell into dilapidation and neglect by the colonial government, with significant budget cuts and discharging of more than eighty-percent of the Militia's active service-members, the defense force became a shadow of its former self. Morale and discipline reached an all-time low, and the Militia would suffer controversy after controversy in the early-2520s. Harassment, bullying, discrimination, and sexual crimes became a common occurrence throughout the Militia's ranks, after media coverage and public outrage worsened the situation, the United Nations Space Command and Colonial Administration becoming involved; threatening to shut down the Militia as a consequence to the ongoing controversies and self-destructive policies put into place over the past ten years.

Beginning in 2524, the UNSC began an oversight and restructuring program of the Militia, intended to erase the defense force's bad history and improve its public image. The Militia's defense budget was increased at the request of the CAA and UNSC, and over the next three years, the Militia underwent rigorous training and exercises. By 2528, the Mazovian Militia had become a proper and disciplined fighting force. The arrival of the Covenant and its impact on society played a major role in reshaping the Militia, attitudes became more serious, strained, and mature as the shadow of the alien threat loomed over humanity.

UNSC Garrison

Law Enforcement


Food & Agriculture


Raw & Industrial Materials

Finished Goods



Tourism and Gambling



Ethnicity & Languages


Notable Mazovians


Fauna of Mazovia

Flora of Mazovia


Notable Geographical formations


Notable locations

  • City of Toruń
    • Ciderhill - Agricultural district.
    • Downtown Toruń - Also known as Lower Toruń. City center.
    • Financial District - Financial and office center.
    • Jesień Island - (Translation: Autumn) High-income residential area.
    • Kampus Scientifica - Scientific research center and military installation.
    • Lake Town - High-income residential area.
    • Midway District - Sports center and Mall.
    • Nowy Toruń - (New Toruń) Suburb.
    • Riverside Borough - Middle-income residential area.
    • Riverview Park - Urban park.
    • Silver Coast - Low-income residential area.
    • Toruń Intercontinental Airport and Spaceport (TIAS)
    • Toruń Port - Main harbor.
    • Ułan Park - Middle-income residential area.
    • Uniwersytet Torunia - (Translation: University of Toruń).
    • Winnica - (Translation: The Vineyard) Agricultural district and residential area.
    • Żółtyogród - (Translation: Yellowgarden) - High-density middle-income residential area and industrial district.


Community content is available under CC-BY-SA unless otherwise noted.