The Lyran Alliance is a fictional state in the BattleTech universe. Formely the Lyran Commonwealth it was created as a result of Kathrine Steiner-Davion using a cluase within the alliance that formed the Federated Commonwealth to break away the lyran part.
The Lyran Commonwealth was formed by the merger of the Tamar Pact, the Alliance of Donegal, and the Federation of Skye. The original capital of the Lyran Commonwealth was Arcturus, but the throne was transferred to Tharkad in 2406, where it has remained ever since. The Lyran Commonwealth was ruled for most of its history by House Steiner.
===Lyran Alliance The catalyst for the secession of Lyran worlds from the FedCom was the death of young Joshua Marik, heir to the Free Worlds League. Ill with leukemia, Joshua died while undergoing treatment at the New Avalon Institute of Science. His death came at a delicate time, with the Clans chafing at the fifteen-year Truce of Tukayyid and the treaty itself set to expire a mere decade.
In addition, Joshua's demise left his half-sister Isis as heir presumptive to the Free Worlds throne. Isis Marik's engagement to Sun-Tzu Liao, Chancellor of the Capellan Confederation, raised the specter of the ambitious Capellan leader controlling the League's army and industrial production.
Faced with this dilemma, Victor Steiner-Davion made a fateful error in judgment. Substituting a double for Joshua. An enraged Thomas Marik learned of the deception and promptly declared war on the FedCom. An apparently shocked Katherine disavowed Victor and proclaimed Lyran neutrality in the conflict. Along with that neutrality came a declaration of secession; henceforth, Lyran territory would no longer be part of the FedCom, but would instead be known as the independent Lyran Alliance.
Primed by anti-Victor rumors and the upheaval of recent years, most Lyran citizens welcomed the break. Victor and his loyal military units were too preoccupied with the Clans to undo the secession by force, and so the Lyran people had little fear of civil war.
In 3067, after Katherine Steiner-Davion was deposed, her brother Peter took up the post of Archon, and renamed the nation as the Lyran Commonwealth as a way to divorce the nation from the more totalitarian rule enforced under the deposed Archon-Princess' rule.
- Stackpole, Michael A. (1995). Bred for War. Roc Books.