From Warhammer 40k - Lexicanum
The Zambeque Rebellion was an anti-Imperial uprising on the world of Zambeque in 883.M37.
Beginning after the Governor was approached by the Dark Angels 5th Company for questioning, upon their arrival the planet declared open rebellion. The Dark Angels task force was soon surrounded in an ambush by Alpha Legion Chaos Space Marines. Only the timely intervention of half the Deathwing prevented the annihilation of the 5th Company. After the battle it was revealed that the Governor was a Fallen Angel known as Solas, who escaped with the remnants of his Chaos Space Marine allies before the planet fell back into the Imperial fold.
- 1: Codex: Dark Angels (6th Edition), pgs. 36-37