The Eisenstein was a frigate of no great size or renown, a mere escort vessel among the vast war-fleets of the Death Guard, and yet it would earn a place in Imperial history greater than many a battleship. For it was aboard this modest ship that Captain Nathaniel Garro made his desperate bid to warn the Emperor that the Warmaster had betrayed Him. Its name became a byword for loyalty against impossible odds.
When the horror of the Isstvan III atrocity unfolded and the loyal sons of the traitor Legions were marked for death, Garro gathered the faithful he could reach and seized the Eisenstein. Breaking from the fleet under fire, the frigate ran the gauntlet of the traitor armada, its shields buckling and its hull scarred, carrying its precious warning into the void.
To escape, Garro ordered the ship to make a blind, reckless plunge into the warp, and there it languished, becalmed and besieged by daemonic horrors that clawed at its wards. Only through faith and sacrifice did the vessel and its survivors endure the crossing.
At last the Eisenstein limped to the Solar System, and Garro delivered his testimony to the loyalist commanders. That single frigate's flight bought the Imperium precious time to prepare, and its name endured as a symbol of the loyalty that no treachery could wholly extinguish.