Once an Imperial naval depot, Nova Mercia waned in importance with the decline of the March, before being overrun by the Neo-Republicans during the Antaran Succession crisis. After its liberation by Admiral Buckingham, the system became the capital of his newly formed domain, and to this day serves as the official headquarters of the Buccaneers.
It would be a mistake, however, to think that a swift strike on this relatively vulnerable system on the edge of the March would cripple the Buccaneers. Their true military base is located deep inside the March, hidden amongst the shifting debris of stellar births and deaths where only the most determined would find it, were they willing to risk the wrath of the Buccaneers by trespassing so deep into their dominion.
Nova Mercia's true importance is its ease of access: while local ships can navigate to the distant colony worlds with ease, freighters from outside the March would swiftly find themselves hopelessly lost. Nova Mercia thus serves as the hub of trade, connecting the worlds of the March with the markets of the greater Empire.
It is also where official, and unofficial, contact can be made with the Buccaneers, and there are rumours that there is a thriving black market in information and deniable assets in the shadier parts of Nova Mercia. Despite infrequent attempts to pin anything formally to the Buccaneers, they have always managed to distance themselves from accusations of aiding and abetting the pirates operating near the March, often proving their loyalty, and their accuser's ineptitude, by hunting down the pirates they stand accused of supporting, and delivering them to their accusers.