Sacnoth is a major world in the Sword Worlds Confederation (or 'Schwertwelt Bund') on the Spinward Marches border of the Imperium. It is a medium-sized world with a tainted standard atmosphere, and half of its surface covered by water. The 8 billion inhabitants live in a number of underwater arcologies and orbital stations. They are ruled by a series of advisory councils ('Neuvosto') comprised of experts in various fields. A panel of high ranking judges forms the Legal Advisory Council ('Ligilneuvosto'), a board of company directors forms the Trade & Industry Advisory Council ('Företagneuvosto'), a committee of senior bank officials forms the Economic Advisory Council ('Byråneuvosto'), and so on. Disputes between the Advisory Councils are settled by Baron Raine hault-Saemund Mayer of House Mayer. Sacnoth's primary agricultural output is fish, but the inhabitants supplement their diet with game (hunting is a common passtime).

Karl Anders hault-Raine Mayer is the son of Baron Saemund hault-Raine Mayer and Lady Guilda Schnorr-Mayer (of House Mayer). He has an older brother Calder William hault-Raine Mayer. At age 10 he was fostered by Baron Hermann Karlstad of Sting and his wife according to Sword World tradition for second sons. As such he spent his youth in the city of Lubeck on Sting (small world, thin atmosphere, 50% water, 300 million inhabitants, governed by an impersonal bureaucracy).

Karl Mayer is a Sword Worlder in the classical sense: driven and arrogant, he does not tolerate failure in himself or others, and suffers from overconfidence. The House Mayer family motto "Honour, Duty, Glory" is his creed.

Despite being the second son he has been awarded by his father the family duelling sword made from a shard of hull material (bonded superdense) from the original colonisation ship (the Valparaiso). The sword is called 'Unserschwert' (trans. 'Our Sword') and is a symbol of House Mayer's dominance and internal unity.

Karl Mayer attended College on Sting and obtained a commission in the Sword Worlds Defense Force ('Schwertwelt Defensivkraft' or SWDK). He has served three terms as a combat engineer and an internal security operative in both the Sacnoth Armed Forces ('Sacnoth Zweigkraft' or SZK) and the Sting Military Force ('Sting Wehrkraft' or SWK). In that time he has been awarded the Bronze Cross twice and the Silver Cross.

At age 31, an internal security investigation into Admiral-elect Wolfgang Zahn resulted in Karl Mayer's courtmartial by then Admiral Strucker. In the trial he was able to clear his name and earn a promotion. Zahn did not become Admiral of the SWDK, but Admiral Eriksson and Admiral Tryggvesson jointly did.

During the Fifth Frontier War the SWDK formed the Sacnoth Fleet (under Tryggvesson) and the Narsil Fleet (under Eriksson). The Sword Worlds corporation United Energy and Transport (UET) formed the Joyeuse Fleet under their CEO Admiral Eyolfsson, and Admiral Riksdattar (a senior politician in the Schwertwelt Bundrat) raised the Gram Fleet from assets transferred from the SWDK and donations from other Houses. As an officer in the SWDK, Karl Mayer is serving in the Sacnoth Fleet.