Leonis
Heart of the Colonies
Leonis was the largest world in the Cyrannus star system and one of the Twelve Colonies of Kobol. Known as the "Heart of the Colonies", it was the seat of a former empire, renowned for its wine, ski slopes and learning, and was left uninhabitable by the Cylon assault.
Leonis, known as the "Heart of the Colonies" and originally named Leo, was a highly temperate world and the physically largest in the Cyrannus star system, orbiting the star Helios Beta. It was one of the Twelve Colonies of Kobol, named after the Leo tribe who had resided on Kobol, though its citizens may not have been affiliated with that tribe. The seat of one of two great early empires, Leonis was renowned for its wine, ski slopes and centers of learning before it was rendered uninhabitable in the Fall of the Twelve Colonies.
The Leonese empire#
In the centuries following the Gemenese dark age and the colonization of other worlds, Leonis and Virgon emerged as two powerful empires that controlled several other planets. Each colonized many worlds, spreading their culture across the four star systems. A number of conflicts were fought over control of these planets, including Libran, Picon, Sagittaron, Scorpia, Tauron and Troy. Fighting on Tauron around the late 11th century resulted in an independent Tauron run by Tauronised settlers. Both empires finally collapsed in the 18th century, with Leonis becoming a republic. By the 19th century its relations with Virgon had warmed, while its relations with the formerly Virgon-aligned Picon remained problematic. The patron god of Leonis was Artemis, daughter of Zeus and sister of Apollo.
The Cylon War and the Fall#
By roughly half a century before the Fall, a sentient robotic slave race known as the Cylons had become ubiquitous in human society. Driven by monotheist radicalization, they launched a system-wide slave revolt that developed into a mutually genocidal conflict. Facing extinction, Leonis and the other eleven sovereign worlds united their militaries and resources to form the United Colonies of Kobol. After twelve years the Cylon War ended, and Leonis continued as part of a federal interplanetary state.
Around the year of the Fall, the Cylons returned and, using advanced hacking abilities, disabled the Colonial Fleet and destroyed Leonis' cities in a nuclear bombardment. While some of its people escaped into a refugee fleet, those left behind were exterminated by Centurions or captured and experimented on in the Farms. Following the abandonment of Cylon colonization efforts almost a year later, Leonis is believed to have had no human survivors.
Geography and landmarks#
With almost no axial tilt, Leonis had a mild and predictable climate before the nuclear winter. Beaches near the equator stayed warm while mountains toward the poles stayed cold, allowing year-round tourist destinations. The warm tropics also produced Leonan wine, considered to be of fine taste.
In the 19th century Leonis had two major cities, Luminere and Hedon, of which Luminere served as the capital. Hedon became a popular tourist destination across the Twelve Worlds because of its Grand Casino, while the Royal Palace of Leonis was an important cultural attraction.
Frequently asked questions
- What was Leonis?
- Leonis, known as the Heart of the Colonies and originally named Leo, was a highly temperate world and the physically largest in the Cyrannus star system, orbiting the star Helios Beta. It was one of the Twelve Colonies of Kobol.
- Why was Leonis known for keeping its own language?
- Unlike most colonies, which adopted Caprican as their standard tongue, Leonis kept its own language, Leonese, into the 19th century.
- What was the Leonese empire?
- Leonis and Virgon emerged as two powerful empires that controlled several other planets and spread their culture across the four star systems. They fought conflicts over worlds including Libran, Picon, Sagittaron, Scorpia, Tauron and Troy, and both empires collapsed in the 18th century, leaving Leonis a republic.
- What happened to Leonis in the Fall of the Twelve Colonies?
- Around the year of the Fall, the Cylons used advanced hacking abilities to disable the Colonial Fleet and destroyed Leonis' cities in a nuclear bombardment. Some of its people escaped into a refugee fleet, while those left behind were exterminated by Centurions or captured and experimented on in the Farms, and Leonis is believed to have had no human survivors.
- What was Leonis known for before the Fall?
- Leonis was renowned for its wine, ski slopes and centers of learning. Its mild climate allowed year-round tourist destinations, and its two major cities were Luminere, the capital, and Hedon, a popular tourist destination known for its Grand Casino.
Gallery

Images via Battlestar Wiki
Sources
- WikiLeonis — Battlestar Wiki entry
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