From Warhammer 40k - Lexicanum
The Lagan System is a System of the Imperium. Located on the Eastern Fringe, the System was occupied by the Tau Empire sometime before late M41. The Lagan System was rapidly developed by the Tau, and eventually graded a Class 1 Colony.
- 1: Codex: Space Marines (5th Edition), pg. 40
- 2: Codex: Tau Empire (7th Edition) - Relentless Expansion