Tarsonis: the world Mengsk fed to the zerg

Tarsonis was a temperate planet in the Koprulu sector and the founding world of terran civilization there, the seat of government and economy for the Terran Confederacy. It was the first of the colony worlds settled by the survivors of the supercarrier Nagglfar, and from it the terrans spread across the sector. Tarsonis remained the densely populated heart of the Confederacy until 2500, when Arcturus Mengsk lured the zerg to the planet with psi emitters and abandoned Sarah Kerrigan to the Swarm, an act that brought down the Confederacy and cleared his path to power. (StarCraft; Koprulu Sector Systems: Tarsonis; StarCraft II: Wings of Liberty)

Early settlement#

When the supercarrier Nagglfar crash-landed on Tarsonis, its passengers accessed the ATLAS computer directly and confirmed their growing suspicion that they would never see Earth again. They stripped the Nagglfar of essential materials to survive in what they termed the New World, and the ruling class, the commanders of the ship, held that maintaining law and order was critical; the police district headquarters were built from pieces of the original colony ships. The vagabond inhabitants expanded quickly, establishing cities and industry across much of the surface and spreading to other worlds, developing a prosperous, self-supporting economy. (StarCraft; StarCraft: Ghost: Nova; Koprulu Sector Systems: Tarsonis)

After living in isolation for sixty years, the Tarsonians developed second-generation subwarp engines that allowed contact with Moria and Umoja. Tarsonis was the most technologically advanced and prosperous of the three colonies, having been given a head start by ATLAS. It pushed for a conglomerated government, but Moria and Umoja refused, fearing Tarsonian dominance. The Old Families responded by expanding their military and colonizing more aggressively, founding prosperous colonies on seven other worlds, and Tarsonis and its colonies founded the Terran Confederacy. (StarCraft; Koprulu Sector Systems: Tarsonis)

The Confederate capital#

As the central hub of the Confederacy's governance and economy, Tarsonis held its most potent defenses in orbit. Three primary orbital platforms served as staging areas for the Confederate fleet, the central platform defended by Omega and Delta Squadron troops, with the ion cannon as the primary defensive weapon. Over time these defenses were engaged in over thirty major battles. At the height of Confederate power, huge quantities of money and materials were shipped in from the colonies daily, and the economic boom dwarfed that of any other terran world in the sector until Tarsonis became one of the most densely populated planets there. (StarCraft; Koprulu Sector Systems: Tarsonis)

The fall#

In 2500 Alpha Squadron assaulted the central platform, and General Edmund Duke planted psi emitters to lure the zerg. Adjutant 23-46 intercepted a transmission revealing that Arcturus Mengsk had authorized the use of those emitters. Billions of zerg arrived in the Tarsonis system and began their invasion, quickly overrunning the planetary defenses and devastating the major cities and industrial centers. (StarCraft; StarCraft II: Wings of Liberty; StarCraft Field Manual; Koprulu Sector Systems: Tarsonis)

The zerg set up their primary hive where Executor Tassadar deployed ground forces to engage them. Mengsk sent a strike force led by Lieutenant Sarah Kerrigan to stop Tassadar's interference. Kerrigan neutralized the protoss, but a wave of zerg advanced on her position; when she called for immediate evacuation, Mengsk ordered the Sons of Korhal fleet to move away from Tarsonis, abandoning her to the zerg. Captain Jim Raynor rushed to Tarsonis to save her but found no trace. The Sons of Korhal rescued a number of civilians from the last functioning space port, Osborne Port, but an estimated two billion people were killed. The protoss and zerg battled across the core continent until the zerg abandoned the planet and the Conclave bade Tassadar return to Aiur. (StarCraft; StarCraft II: Wings of Liberty; StarCraft: Ghost: Nova; Koprulu Sector Systems: Tarsonis)

The Brood War and after#

During the Brood War the United Earth Directorate research team uncovered the psi disrupter on Tarsonis. Lieutenant Samir Duran destroyed four zerg hives before locating it, then was relieved by ghosts under orders from Vice Admiral Alexei Stukov to disassemble the disrupter and reconstruct it on Braxis. Kerrigan later established a fortress on Tarsonis and contacted Raynor and Fenix, but the disrupter's signal shattered the unity of her broods, which turned on each other across her seven hive clusters. After driving the UED from Korhal, Kerrigan returned to rest on Tarsonis before abandoning it and relocating to Char. (StarCraft: Brood War)

The Terran Dominion placed Tarsonis under strict quarantine while salvage teams sifted the rubble for surviving Confederate technologies and military secrets. Feral zerg continued to thrive on the planet, even producing new breeds, and Tarsonis became a hideaway for criminal groups such as the Scantid Pirates. During the Second Great War the Dominion ran supply trains across the restored rail network, and Raynor's Raiders raided one to recover Adjutant 23-46. After the End War a separatist group called the Defenders of Man established a base in Tarsonis City, where Nova Terra later uncovered their plan to use psi emitters against civilian worlds to undermine Emperor Valerian Mengsk. (Koprulu Sector Systems: Tarsonis; Just an Overlord; StarCraft II: Wings of Liberty; StarCraft II: Nova Covert Ops)