From Lexicanum

The background on Hylgar's Hell-raisers comes from early 1st edition - back when the Imperial Guard was known simply as the "Imperial Army" - and contradicts organizational and equipment-technical characteristics in the current background. In addition its commander Hylgar carried both Ecclesiarchial and military ranks, which was forbidden since the Age of Apostasy.

Hylgar's Hell-raisers were originally presented as a typical army of the Imperium (circa 1988); Third Edition's second Imperial Guard codex also mentions this old regiment, describing the implausibility of such an army, concluding that it actually existed before the Heresy - before the Ecclesiarchy itself existed.

The 13th/5th Imperial Army, also known as Hylgar's Hell-raisers, is the 13th army of the 5th quadrant. It is commanded by Julius Hylgar "of the Priesthood of Earth," who is a senior member of the Administratum. He carries the titles "Cardinal of Kolarne" and "Grand Marnier Militaris". The latter is a Priesthood title; the military branch of the Administratum being the "Administratus Militarium".

The army consists of 12 Brigades, which are garrisoned in the Kolarne system. Each brigade is under the command of a Brigadier-General and is divided into ten companies, each under the command of a captain. The 10th Company had the task of maintaining order in Kolarne and protecting the sector from Eldar and Orks.

The army contains a number of abhumans serving beside Imperial soldiers including Squats and Ogryns. The army also fields heavy armour and weapons including Land Raiders, Land Speeders, Rapiers, Tarantulas and Mole Mortars.

Known squad types of the 10th Company of the 13th/5th Imperial Army

"Cyclones" - Assault Squads
"Destroyers" - Ogryn Squads
"Eagles" - Recon Squads
"Forge Fires" - Squat Tactical Squads
"Hurricanes" - Guard Squads
"Iron Hammers" - Squat Striker Squads
"Thunderbolts" - Squat Assault Squads
"Tornadoes" - Tactical Squads
"Volcanoes" - Squat Guard Squads
"Whirlwinds" - Striker Squads

Source

• Chapter Approved: Book of the Astronomican
• Codex: Imperial Guard (3rd Edition, 2nd Codex)