Inception
Prior to the inception of the fourth succession war the Federated Suns maintained several elite expeditionary regiments operating in the Capellan and Draconis Marches. These units were tasked with probing and assessing enemy combat readiness along the borders of the Federated Suns. To hide their true intent and origins these regiments often deployed smaller company sized units that were organized and operated to resemble mercenary units and often conducted elaborate raids on mundane border world resources while small detachments would sneak off and assess the battle from a distance, observing the unit-makeup and tactical doctrine of the planetary defenses forces, meeting with local dissident groups and planting the seeds for an insurgency.
Upon the announcement that Hanse Davion and Melissa Steiner would marry orders started coming down redeploying these units coreward and anti-spinward along the Capellan and Draconis Marches over a span of many months. No one took much notice of these small “mercenary” company redeployments as these types of units were well known to move from contract to contract. The redeployed units eventually fell under the banner of a shadow unit designation known as the “Coreward Operational Region Expeditionary Division,” or “CORE Division” for short. Through subterfuge and patience the Federated Suns had mobilized an entire division of its forces in preparation for what would later be known as the fourth succession war.