Erich Sheridan was a minor noble on Kaumberg, a planet in the Alarion Province of the Lyran Alliance. He came power following a 3063 civil war between the two most powerful noble families on the planet, the Hassledorfs and LeSats. Though the Hassledorfs won that fight, Trent Hassledorf declined the position. Sheridan rose to power as a compromise. As Lord of Lords, Sheridan quickly proved himself capable, convincing the nobles to work together to rebuild.
Sheridan ordered the Kaumberg Planetary Guard into action on 27 July 3071 in response to a plea for help from Landgraf Karl von Weinmann on Enzesfled. A militant faction of the Democracy Now movement led by Lindon Ashley had ousted the nobility from power. Citing the Firenze Regional Defense Pact, Sheridan sent the KPG, commanded by Baron Trent Hassledorf, to Enzesfled.
Sheridan was thrust into the limelight in 3072 when Archon Peter Steiner-Davion resurrected an idea from the early 29th century: Archonettes. Kaumberg was one of the first four Archonettes to be formed by the Archon, empowering Sheridan to help fourteen of his neighboring planets rebuild. Sheridan wasted little time utilizing his new authority to essentially declare war on Democracy Now and order the KPG to Novara, home to the headquarters of Democracy Now. Speaking from the planetary capital of Stuttgart, Sheridan said that time had "run out" for Ashley and his followers. The KPG was easily victorious over Ashley's Democratic People's Army, though they failed to capture him.
Two years later, Ashley reappeared on Virtue, again espousing his ideals. The KPG was scattered, training the defenders of the Archonette. Unable to respond immediately, Sheridan could only watch as Ashley's views again spread through his Archonette, this time in force, to Vermezzo and Akfata. In May 3075, Sheridan personally led KPG forces against Ashley's supporters on Akfata. Directing the assault from orbit, Sheridan's KPG contingent brought their full weight to bear against target after target, rolling up the DPA, who possessed unexpectedly high numbers of both 'Mechs and 'Mechs that fielded advanced technology. They secured the main DropPort, then a strategic mountain pass, and finally moved on the planetary capital. The DPA fought hard and resolutely, but fell to the KPG on 2 May 3075. Sheridan's forces had completely liberated Akfata in thirty-seven hours.
With his forces damaged from the fighting on Vermezzo and Akfata, Archonette Sheridan hired mercenary unit Kirkpatrick's Invaders a few weeks after the battles. The Invaders and KPG assaulted Virtue in August and captured Lindon Ashley after two weeks of fighting. After a trial for crimes against the Alliance, he was executed in January 3076. Sheridan personally read out Ashley's crimes at the execution.
In 3081 Archon Adam Steiner disbanded the Arcturus and Buena Archonettes, though others, including Kaumberg and Inarcs, refused to relinquish their power. In April, the Kaumberg House of Lords publicly called for Sheridan to retire the Archonette, though he refused. It took the use of military force against Inarcs before Sheridan returned his Archonette powers to the Archon.
- Operation: Flashpoint, pp. 84-85, "Brother Against Brother"
- Masters and Minions: The StarCorps Dossiers, p. 88, "Erich Sheridan"
- Jihad Hot Spots: 3072, p. 41, "Aftermath" & p. 46, "Police Actions"
- Jihad Hot Spots: 3072, p. 94, "Return of the Archonettes" & "Declaration of War"
- Field Report: LAAF, p. 19
- Jihad Hot Spots: 3076, p. 52, "Timeline of the Jihad"
- Jihad Hot Spots: 3076, pp. 23-24
- Jihad: Final Reckoning, p. 54, "The Jihad in Review"
- Jihad Hot Spots: 3076, pp. 71-72, "Democracy Now Trials Begin on Kaumberg" & p. 74, "Execution for Ashley, Conspirators"
- Jihad: Final Reckoning, p. 61, "The Jihad in Review"
- Field Manual: 3085, pp. 94-95, "Reclaiming Authority"