First Ruin

The First Ruin was a period of three years, 009 to 011.M31, which saw the first instance of civil war between the Legiones Astartes. The First Ruin marked the end of the Halcyon Age, a decade of rebuilding and the attempt to restart the Great Crusade. However, personal and ideological disagreements between Primarchs and the Council of Terra led to a spiralling political crisis over the issue of whether a new Emperor should be crowned. As the Imperial high command was distracted by this, a tangentially related event turned into a massacre between three legions and the apparent death of a Primarch. The shocking news of the Breaking of Keld'abe rocked the Imperium, the veneer of civility and unity having been shattered and fear over the future growing.

Prelude
The seeds that would grow into the First Ruin were spread through the previous decade back to the Vanishing.

Key Events
[[Category:F]]
 * Succession Crisis (009-011.M31)
 * Breaking of Keld'abe (011.M31)
 * Trial of Araphel (011.M31)