Bakka

Bakka is the Imperial Naval Base for Segmentum Tempestus. It co-ordinates all naval forces in the region and dispatches ships when needed.

In 745.M41, during the Tyrannic Wars (Battle of Macragge), a battlefleet was dispatched to Macragge to help defend it. They were ultimately successful, but suffered heavy losses to the aliens.

Also, in 300.M36, Bakka was absorbed into the Plague of Unbelief, forming a minor empire which believed the Emperor was no longer able to rule the galaxy, stretching from Bakka in the galactic south to Fenris in the galactic north. This was eventually destroyed by the Space Wolves after a protracted fight at The Fang fortress.