The Containment

The Containment was a massive Imperial campaign conducted by the Sons of Iron Space Marine Chapter to help contain a massive incursion of various pirates and xenos that threatened the heart of the Imperium.

History
Hordes of pirates, xenos and other scoundrels flee towards the centre of the galaxy and try to enter Imperial Space. The Sons of Iron mount a defense which ensures that most of the ill-equipped and out-gunned invaders are repelled, even if many a spaceship manages to slip through their net. During those thirty years, the Reserve Companies spent most of their time fighting, insuring a great deal of experience to their recruits. In the same time, many a battle-brother in the Battle Companies is dispatched to the Deathwatch.

The massive exodus cease as suddenly as it has begun. Scouting forces from the Sons of Iron enter the regions of space emptied by their inhabitants. There, they discover only barren worlds, still reeling from massive destruction. Some seem to have been destroyed by means of weapons but others have even lost their atmosphere and all biomass. The Chapter assumes that some unknown xeno threat destroyed the worlds and returns to its routine of protecting the Imperium.