Gervhart was not only a fierce warrior but also a master tactician and student of history (second only to the Chapter's archivists in his knowledge and understanding of the ancient days of the Imperium).[Needs Citation] He had studied the ways of war of every Marshal since the time of Sigismund and was well versed in the most arcane weapons and wargear.
He was also responsible for conducting the Athelor Crusade. While prosecuting this crusade, he ordered the construction of Montgisard, a chapter keep located on the planet Stygia XII, which would serve the Chapter well for thousands of years before being abandoned.
- Note 1: Gideon Amesaris, a Reclusiarch of the Black Templars who served under Gervhart, was stated by Chaplain Mathias Vlain to have had a hand in constructing one of the vaults beneath Montgisard "almost four thousand years ago" in the short story And They Shall Know No Fear..., which is set in 832.M41. This would imply that Gideon (and by extension Gervhart) served during late M37 or possibly early M38.