Galenius was a veteran sergeant of the 1st company of the Blood Angels Legion during the Horus Heresy and was noted to have earned many honours by the time of the Siege of Terra.
He was part of the escort that accompanied Sanguinius to meet Fabricator General Zagreus Kane and became furious when his Primarch was made to wait by order of the newly established Adeptus Mechanicus and demanded the Skitarii Mandragora to move, but to no avail. Sanguinius advised Galenius to maintain calm and explained to him that this was a political move from the martian mechanicus. The sergeant obeyed and admitted that his temper got the better of him. Sanguinius, then, suggested that he should have transferred the sergeant to Captain Amit's company. Galenius laughed at this suggestion saying his Primarch was not the first to make it and that he thought that Captain Raldoron only kept him to remind himself why he didn't like Captain Amit.
- 1: The Lost and the Damned (Novel), Chapter 8